US20060083329A1 - Methods and systems for utilizing universal frequency translators for phase and/or frequency detection - Google Patents

Methods and systems for utilizing universal frequency translators for phase and/or frequency detection Download PDF

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US20060083329A1
US20060083329A1 US11/292,118 US29211805A US2006083329A1 US 20060083329 A1 US20060083329 A1 US 20060083329A1 US 29211805 A US29211805 A US 29211805A US 2006083329 A1 US2006083329 A1 US 2006083329A1
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frequency
phase
d2d
signal
equalizer
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David Sorrells
Michael Bultman
Robert Cook
Richard Looke
Charley Moses
Gregory Rawlins
Michael Rawlins
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ParkerVision Inc
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ParkerVision Inc
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Priority to US17770500P priority
Priority to US17770200P priority
Priority to US18066700P priority
Priority to US09/525,615 priority patent/US6853690B1/en
Priority to US11/015,653 priority patent/US7773688B2/en
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/02Transmitters
    • H04B1/04Circuits
    • H04B1/0475Circuits with means for limiting noise, interference or distortion
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03CMODULATION
    • H03C3/00Angle modulation
    • H03C3/38Angle modulation by converting amplitude modulation to angle modulation
    • H03C3/40Angle modulation by converting amplitude modulation to angle modulation using two signal paths the outputs of which have a predetermined phase difference and at least one output being amplitude-modulated
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03DDEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D3/00Demodulation of angle-, frequency- or phase- modulated oscillations
    • H03D3/006Demodulation of angle-, frequency- or phase- modulated oscillations by sampling the oscillations and further processing the samples, e.g. by computing techniques
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03DDEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D7/00Transference of modulation from one carrier to another, e.g. frequency-changing
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/02Details ; Arrangements for supplying electrical power along data transmission lines
    • H04L25/03Shaping networks in transmitter or receiver, e.g. adaptive shaping networks ; Receiver end arrangements for processing baseband signals

Abstract

Systems and methods for utilizing universal frequency translators within gated energy transfer systems for phase detection and/or frequency detection. Phase and/or frequency detection can be utilized for comparing a higher frequency reference signal with a lower frequency local oscillator signal. Phase and/or frequency detection can also be utilized for phase locking and/or frequency locking. The systems and methods can be utilized to simultaneously downconvert a reference signal for phase and/or frequency comparison and/or for locking, at lower Phase and/or frequency detection can be utilized for frequencies, which is easier to design and which requires less expensive electrical components.

Description

    CROSS-REFERENCE TO OTHER APPLICATIONS
  • This application is a continuation of pending U.S. application Ser. No. 11/015,653, filed Dec. 20, 2004 (Atty. Docket No. 1744.0450004), which is a continuation of U.S. application Ser. No. 09/525,615, filed Mar. 14, 2000, now U.S. Pat. No. 6,853,690, and which claims the benefit of U.S. Provisional Application No. 60/177,381, filed Jan. 24, 2000; U.S. Provisional Application No. 60/171,502, filed Dec. 22, 1999; U.S. Provisional Application No. 60/177,705, filed Jan. 24, 2000; U.S. Provisional Application No. 60/129,839, filed Apr. 16, 1999; U.S. Provisional Application No. 60/158,047, filed Oct. 7, 1999; U.S. Provisional Application No. 60/171,349, filed Dec. 21, 1999; U.S. Provisional Application No. 60/177,702, filed Jan. 24, 2000; U.S. Provisional Application No. 60/180,667, filed Feb. 7, 2000; and U.S. Provisional Application No. 60/171,496, filed Dec. 22, 1999, all of which are incorporated by reference herein in their entireties.
  • BACKGROUND OF THE INVENTION
  • 1. Field of the Invention
  • The present invention is generally related to methods and systems for utilizing universal frequency translators for phase and/or frequency detection.
  • 2. Related Art
  • Prior art methods and systems for frequency translation and phase and/or frequency detection exist.
  • BRIEF SUMMARY OF THE INVENTION
  • Briefly stated, the field of the invention is directed to methods and systems for utilizing universal frequency translators for phase and/or frequency detection.
  • Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings. The drawing in which an element first appears is typically indicated by the leftmost character(s) and/or digit(s) in the corresponding reference number.
  • BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
  • The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. Generally, in the drawings, like reference numbers indicate identical or functionally similar elements. Additionally, generally, the leftmost digit(s) of a reference number identifies the drawing in which the reference number first appears.
  • FIG. 1 illustrates an example phase difference detector.
  • FIG. 2 illustrates an example phase locked loop.
  • FIG. 3 illustrates an example compensation module of the phase locked loop shown in FIG. 2.
  • FIG. 4 illustrates an example frequency difference detection module.
  • FIG. 5 illustrates an example frequency locked loop.
  • FIG. 6 illustrates an example loop filter of the frequency difference detection module shown in FIG. 5.
  • FIG. 7 illustrates an example carrier acquisition and tracking module with D2D.
  • FIG. 8 illustrates an example baseband symbol clock recovery module with D2D.
  • FIG. 9 illustrates example transversal equalizer demodulator and modulator configurations.
  • FIG. 10 illustrates an example baseband linear transversal equalizer LMS implementation.
  • FIG. 11 illustrates an example baseband linear transversal equalizer zero forcing implementation.
  • FIG. 12 illustrates an example zero forcing D2D implementation.
  • FIG. 13 illustrates an example RF or passband linear transversal equalizer LMS implementation.
  • FIG. 14 illustrates an example RF or passband linear transversal equalizer zero forcing implementation.
  • FIG. 15 illustrates an example zero forcing D2D implementation.
  • FIG. 16 illustrates an example D2D spreader/despreader configuration.
  • FIG. 17 illustrates example waveforms for a D2D spreader/despreader.
  • FIG. 18 illustrates a first example implementation of a D2D spreader/despreader.
  • FIG. 19 illustrates a second example implementation of a D2D spreader/despreader.
  • FIG. 20 illustrates a third example implementation of a D2D spreader/despreader.
  • FIG. 21 illustrates a fourth example implementation of a D2D spreader/despreader.
  • FIG. 22 illustrates a fifth example implementation of a D2D spreader/despreader.
  • FIG. 23 illustrates a block diagram on an example D2D system and modem on a chip.
  • DETAILED DESCRIPTION OF THE INVENTION
  • Table of Contents
    1. Phase Detection
    1.1 Gating Module as a Phase Difference Detector
    1.2 Implemented as a Phase Locked Loop (PLL)
    1.2.1 Controlling the Trigger Point of v(t)
    1.2.1.1 Controlling the Trigger Point
    of v(t) with Phase Delay
    1.2.1.2 Controlling the Trigger Point
    of v(t) with Bias Voltage
    1.2.2. Automatic Gain Control (AGC)
    1.2.3 Using a PLL to Simultaneously Down-Convert
    and Demodulate a Phase Modulated Signal
    2. Frequency Detection
    2.1 Multiple UFTs for Frequency Detection
    2.2 Implemented as a Frequency Locked Loop
    2.2.1 Controlling the Frequency of v(t) with a VCO
    2.2.2 Automatic Gain Control (AGC)
    2.2.3 Using a Frequency Locked Loop to
    Simultaneously Down-Convert and
    Demodulate a Frequency Modulated Signal
    3. Combination PLL and Frequency Locked Loop
    4. Carrier Acquisition and Tracking with D2D
    4.1 Carrier Acquisition and Tracking
    4.2 Carrier Acquisition and Tracking
    4.3 Baseband Symbol Clock Recovery with D2D
    5. Linear Baseband Transversal Equalizer with D2D
    5.1 LMS Algorithm for Convergence
    5.2 LMS Baseband Transversal Equalizer
    5.3 Zero Forcing Algorithm for Convergence
    5.4 Zero Forcing Transversal Equalizer
    6. Linear RF or Passband Transversal Equalizer with D2D
    6.1 LMS Algorithm for Convergence
    6.2 LMS RF or Passband Transversal Equalizer
    6.3 Zero Forcing Algorithm for Convergence
    6.4 Zero Forcing RF or Passband Transversal Equalizer
    7. D2D as a Spreader/Despreader
    7.1 Case 1
    7.2 Case 2
    7.3 Case 3
    7.4 Case 4
    7.5 Case 5
    8. Example Implementations of Gated Transfer Unit
    9. Conclusion
  • The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are illustrated. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the invention to those skilled in the art.
  • 1. PHASE DETECTOR
  • Universal frequency translators (UFTs), as taught and described in U.S. patent application Ser. No. 09/176,022, titled “Method And System For Down-Converting Electromagnetic Signals,” filed Oct. 21, 1998, now U.S. Pat. No. 6,061,551, U.S. patent application Ser. No. 09/293,342, titled “Method And Circuit For Down-Converting A Signal Using A Complementary FET Structure For Improved Dynamic Range,” filed Apr. 16, 1999, now U.S. Pat. No. 6,687,493, and U.S. patent application Ser. No. 09/293,095, titled “Method And System For Down-Converting Electromagnetic Signals Having Optimized Switch Structures,” filed Apr. 16, 1999, now U.S. Pat. No. 6,580,902 (hereinafter referred to collectively as “Related UFT Patents”), all of which are incorporated herein by reference in their entireties, can be utilized as phase and/or frequency difference detectors.
  • 1.1 Gating Module as a Phase Difference Detector
  • FIG. 1 illustrates a gating module 102, as described in one or more of the Related UFT Patents. In FIG. 1, the gating module 102 is implemented and referred to herein as a phase difference detector. The phase difference detector 102 is functionally illustrated with a UFT, or switching module 104, a capacitor 106, and a pulse generator 108. FIG. 1 is intended to functionally illustrate aspects of an embodiment of the present invention. As described in one or more of the Related UFT Patents, the phase difference detector 102 can be implemented in a variety of configurations using a variety of components.
  • In operation, the pulse generator 108 controls the UFT 104 according to a control signal v(t) at terminal 112, to transfer energy from a reference signal s(t) at terminal 110, to the capacitor 106, as described in the one or more of the Related UFT Patents. From the energy, or charge, transferred to the capacitor 106, a difference signal d(t) is provided at output terminal 114.
  • The difference signal d(t) includes a down-converted version of the reference signal s(t). The difference signal d(t) is substantially proportional to a frequency and phase difference between s(t) and v(t). More specifically, as described in one or more of the Related UFT Patents, the frequency of d(t) is substantially equal to the frequency of s(t) minus N times the frequency of the control signal v(t). Thus, when the frequency of s(t) is substantially equal to N times the frequency of v(t), d(t) will be substantially constant. But, when the phase difference between s(t) and v(t) changes, the constant voltage level of d(t) will change.
  • The amplitude of d(t) will depend, in part, on the phase of s(t) when the switch 104 is closed. The switch 104 closes when the pulse generator 108 generates a pulse. The pulse generator 108 generates a pulse when a rising edge of v(t) triggers the pulse generator 108 to generate a pulse. This is referred to as the trigger point of v(t). Thus, the switch 104 closes on trigger points of v(t).
  • Generally, when the trigger point of v(t) is aligned with a maximum point of s(t)'s carrier frequency, s(t) and v(t) are said to be phase aligned, and the amplitude of d(t) will be at a relative maximum. But as the phase difference between v(t)'s trigger point and s(t) increases, the amplitude of d(t) decreases.
  • As a result of the above description, when the frequency of s(t) is substantially equal to N times the frequency of v(t), the gating module 102 can be viewed as a phase difference detector. One use for the phase difference detector 102 is in a phase locked loop, as described below.
  • 1.2 Implemented as a Phase Locked Loop (PLL)
  • The phase difference detector 102 can be implemented as part of a phase locked loop. In an embodiment, the phase detector 102 is used to simultaneously down-convert the reference signal s(t) and detect phase differences. In this embodiment, phase locking occurs at a lower frequency than the reference signal s(t), which reduces component cost and design complexities. In an example, a UFT is implemented in a phase locked loop.
  • FIG. 2 illustrates the phase difference detector 102 from FIG. 1 implemented in a phase locked loop (PLL) 202. The PLL 202 includes a loop filter 204 and a compensation module 206.
  • The loop filter 204 can be designed for desired stabilization and/or response characteristics. Based on the description herein, one skilled in the relevant art(s) will recognize that the loop filter 204 can be designed and implemented in a variety of configurations using hardware, firmware, software, or any combination thereof. In an embodiment, the loop filter 204 includes an integration function that sums successive values of d(t).
  • The compensation module 206 adjusts the phase and/or frequency of v(t), as necessary, to maintain d(t) at a zero. In an embodiment, when the loop filter 204 includes an integration function that sums successive values of d(t), the output of the loop filter 204 is used by the compensation module 206 to maintain the phase and/or frequency of v(t) at a level that maintains d(t) at zero amplitude.
  • In operation, when the trigger point of v(t) is aligned with a zero crossing of s(t), d(t) will be substantially zero. As a result, there will be no change in the output of the integrator/loop filter 204, and thus, the compensation module 206 will make no changes to v(t). But when the phase of s(t) changes relative to the phase of v(t), d(t) will change away from zero, either positive or negative, depending on which direction the relative phases change. When d(t) changes from zero, positive or negative, the output of the integrator/loop filter 204 increases or decreases respectively, causing the compensation module to increase or decrease the phase and/or frequency of v(t). When the trigger point of v(t) is again aligned with a zero crossing of s(t), d(t) will return to zero. When d(t) returns to zero, the output of the loop filter 204 will hold its previous value until d(t) again changes. So long as the output of the loop filter remains constant at its previous level, the compensation module 206 will maintain the phase and/or frequency of v(t) at its previous level. Thus, any relative phase change between s(t) and v(t) are corrected.
  • One use for phase locked loop as described above is for simultaneously down-converting and demodulating a phase modulated signal, as described below. Before discussing simultaneous down-converting and demodulation, exemplary implementation details of the compensation module will be discussed.
  • 1.2.1 Controlling the Trigger Point of v(t)
  • From the description of the v(t) trigger point above, it will be understood that, for phase locking, the relative phase difference between the v(t) trigger point and s(t) is to be controlled. The relative phase difference between the v(t) trigger point and s(t) can be controlled in a variety of ways.
  • 1.2.1.1 Controlling the Trigger Point of v(t) with Phase Delay
  • In an embodiment, the relative phase of v(t) is controlled by controlling a delay of v(t). This can be done with, for example, a voltage controlled oscillator (VCO). Phase delay can be implemented independently or as part of a voltage controlled oscillator (VCO). Based on the description herein, one skilled in the relevant art(s) will recognize how a conventional VCO with phase delay control can be incorporated into the compensation module 206, in order to control the relative phase difference between the v(t) trigger point and s(t).
  • 1.2.1.2 Controlling the Trigger Point of v(t) with Bias Voltage
  • In another embodiment, the relative phase difference between the v(t) trigger point and s(t) are controlled by controlling a bias voltage on v(t). This can be performed with the circuit illustrated in FIG. 3, or functional equivalents thereof. Changing the bias level of v(t) changes the voltage level for all of v(t) so that, for a given phase of v(t), the bias voltage can be adjusted to meet or exceed the trigger voltage of the pulse generator. In an embodiment, a linear region of v(t) is utilized for bias voltage adjustments.
  • 1.2.2. Automatic Gain Control (AGC)
  • Phase difference detection can be affected by unintentional amplitude variations due to, for example, amplitude changes on the reference signal s(t), or DC offset voltages. In an embodiment, an automatic gain control (AGC) system is used to maintain relative amplitude control.
  • 1.2.3 Using a PLL to Simultaneously Down-Convert and Demodulate a Phase Modulated Signal
  • When the reference signal s(t) is a phase modulated carrier signal, information is encoded, or modulated, on the reference signal s(t) in the form of phase changes about a carrier frequency. In the PLL 202 of FIG. 2, these phase changes will appear as amplitude changes on d(t). When the loop filter 204 includes an integration-type function, as described above, the output of the loop filter will substantially resemble the information that was phase encoded on the reference signal s(t). Thus, while the PLL 202 maintains the phase relationship between v(t) and s(t), the information is simultaneously available as a demodulated baseband information signal at terminal 208. In an embodiment, the PLL 202 includes an AGC system as described above.
  • 2. FREQUENCY DETECTION
  • Universal frequency translators (UFTs), as taught and described in the Related UFT Patents, can be utilized as phase and/or frequency difference detectors.
  • 2.1 Multiple UFTs for Frequency Detection
  • FIG. 4 illustrates a frequency difference detection module 402, including a gating module 404, low pass filters 418 and 420, and loop filter 422. The dual-switch gating modules 404 is functionally illustrated with universal frequency translators (UFTs), or switching modules, 406 and 408, a pulse generator 410, a delay element 412, and capacitors 414 and 416. As described in one or more of the Related UFT Patents, the gating module 404 can be implemented in a variety of configurations using a variety of components, and is not limited to the functional illustration of FIG. 4.
  • In operation, the pulse generator 410 controls the UFTs 406 and 408, according to a control signal v(t) at terminal 426, to transfer energy from a reference signal s(t) at terminal 424, to the capacitors 414 and 416, as described in the one or more of the Related UFT Patents. The delay element 412 causes the UFT 408 to down-convert s(t) 90 degrees out of phase with respect to UFT 406. UFTs 406 and 408 are thus said to generate in-phase and quadrature-phase (I and Q) information channels 430 and 432, respectively.
  • The I and Q channels 430 and 432 are filtered by LPFs 418 and 420, and then provided to the loop filter 422, which generates the difference signal 428. The difference signal d(t) is substantially proportional to the difference between v(t) and s(t).
  • The loop filter 204 can be designed for desired stabilization and/or response characteristics. Based on the description herein, one skilled in the relevant art(s) will recognize that the loop filter 204 can be designed and implemented in a variety of configurations using hardware, firmware, software, or any combination thereof.
  • In an embodiment, loop filter 422 is implemented so that d(t) is positive when the frequency of s(t) is greater than the frequency of v(t), and negative when the frequency of s(t) is less than the frequency of v(t), with an amplitude that is relative to the difference value. An example implementation of this embodiment is illustrated in FIG. 6, as part of a frequency locked loop, as is described in detail below. The present invention is not limited to the example loop filter 422 illustrated in FIG. 6. The example of the loop filter 422 illustrated in FIG. 6 is not limited to implementations in frequency locked loops. Rather, the loop filter 422 illustrated in FIG. 6 can be implemented in systems other than frequency locked loops.
  • In an embodiment, a frequency difference detector, as described above, is utilized in a frequency locked loop, as described below.
  • 2.2 Implemented as a Frequency Locked Loop
  • The frequency difference detector 404 can be implemented as part of a frequency locked loop. In an embodiment, the frequency difference detector 404 is used to simultaneously down-convert the reference signal s(t) and detect frequency differences. In this embodiment, frequency locking occurs at a lower frequency than the reference signal s(t), which reduces component cost and design complexities.
  • FIG. 5 illustrates a frequency locked loop 502, including the frequency difference detector 404 and a compensation module 504. The compensation module 504 controls v(t), based upon d(t).
  • The compensation module 504 adjusts the frequency of v(t), as necessary. In an embodiment, the compensation module 504 adjusts the frequency of v(t), to maintain d(t) substantially at a zero (i.e., to maintain the frequency of v(t), or a harmonic or sub-harmonic thereof, substantially equal to the frequency of s(t)).
  • In an embodiment, the loop filter 422 or the compensation module 504 includes an integration function, illustrated here as integration module 506, that sums successive values of d(t), the result of which is used by the compensation module 504 to maintain the frequency of v(t), or a harmonic or sub-harmonic thereof, substantially equal to the frequency of s(t)).
  • FIG. 6 illustrates an example embodiment of the frequency locked loop 502, including an example implementation of the loop filter 422. It can be shown that d(t) is positive when the frequency of s(t) is greater than the frequency of v(t), and d(t) is negative when the frequency of s(t) is less than the frequency of v(t). The amplitude of d(t) is relative to the extent of the difference between the frequency of s(t) and v(t).
  • In FIG. 6, point a can be defined as A sin(θA), where θ=∫ ω(t)dt. Since the frequency is of interest here, not phase, A sin(θA) can be written as sin(ωAt).
  • Point b can then be defined as B sin(θB), where θBA-90°. So B sin(θB) becomes cos(θA), which, for frequency detection, becomes cos(ωAt).
  • It follows that:
      • point b is ωAcos(ωAt);
      • point e is −ωAsinAt);
      • point c is ωAcos2At);
      • point f is −ωAsin2At); and
      • point g is ωAcos2At)−(−ωASin2At))=ωA(cos2At)+sin2At)), which equals ωA, since cos2(x)+sin2(x)=1.
  • It can be shown that ωA is proportional to ωs(t)-Nωv(t). Thus, it can be shown that:
      • when ωs(t) is greater than N times ωv(t), ωA is greater than zero; and
      • when ωs(t) is less greater than N times ωv(t), ωA is less than zero.
        ωA can thus be used to control v(t) with respect to s(t).
        2.2.1 Controlling the Frequency of v(t) with a VCO
  • In an embodiment, the compensation module 504 includes a VCO that controls the frequency of v(t), based on d(t). In alternative embodiments, a frequency synthesizer and/or any other frequency generator with frequency control can be utilized.
  • 2.2.2 Automatic Gain Control (AGC)
  • In some electronic systems, it may be desirable or necessary to maintain a constant signal level at some point in the system. To achieve a constant signal level, an AGC may be employed.
  • The signal √{square root over (I2+Q2)}, or any reasonable approximation may be used as the control signal to a controlled amplifier. Here, I and Q are the outputs, possibly amplified and filtered, of I and Q UFT devices. As described previously, √{square root over (I2+Q2)} is directly proportional to the signal strength, and so provides an adequate control signal.
  • 2.2.3 Using a Frequency Locked Loop to Simultaneously Down-Convert and Demodulate a Frequency Modulated Signal
  • When the reference signal s(t) is a frequency modulated carrier signal, information is encoded, or modulated, on the reference signal s(t) in the form of frequency changes about a carrier frequency. In the frequency locked loop 502 of FIG. 5, these phase changes will appear as amplitude changes on d(t). When the frequency locked loop 502 includes an integration-type function, as described above, the output of the integration function will substantially resemble the information that was frequency encoded on the reference signal s(t). Thus, while the frequency locked loop maintains the frequency of v(t) at the frequency of s(t) divided by N, the information is simultaneously available as a demodulated baseband information signal at terminal 508.
  • 3. COMBINATION PLL AND FREQUENCY LOCKED LOOP
  • The phase locked loops and frequency locked loops described herein can be utilized in combination so that a frequency locked loop tracks the frequency of s(t) and a phase locked loop tracks the phase of s(t).
  • 4. CARRIER ACQUISITION AND TRACKING WITH D2D
  • 4.1 Carrier Recovery and Tracking
  • The D2D can readily control the phase of a local oscillator (LO) and the dPHI/dt, which is the frequency. If the LO is placed on-chip, the phase lock loop can be an on-chip analog circuit and this will use less power than a digital signal processing (DSP) solution. Analog solutions are almost always lower power solutions than DSP solutions. Based on classical phase lock loop theory, D2D implementation of the baseband clock recovery will simplify the baseband DSP and lower the power requirements of battery powered telecommunications devices requiring coherent detection schemes. The D2D embodiments described herein can be used to drastically reduce the power and weight and cost over a DSP solution.
  • In the example carrier and acquisition architecture shown in FIG. 7, a D2D circuit is used in three places to perform three different functions. First, the D2D circuit is used as a phase detector to compare the phase of the reference carrier, which is coherent, with the sampling signal. Second, the D2D circuit is used as a control circuit to control the frequency and phase of a sampling LO so as to track the frequency and phase of the incoming signal.
  • Third, the D2D circuit is used to convert a sample of the sampling LO to RF so the D2D at RF can detect the phase difference between the incoming signal and the reference LO.
  • In each of these three implementations, the D2D is configured differently. In the phase detector implementation, the two signals to be compared are input to the RF and the LO (or sampling) inputs. The output that would normally be the demodulated signal (baseband port) is a voltage proportional to the phase and frequency difference of the two signals (note that the average input power of both signals should the same in this case). An automatic gain control (AGC) will probably be required. The output of the phase detector is low pass filtered and the filtered voltage is used to control the second D2D. The control voltage is input to the baseband port and is used to modulate the phase and frequency of the LO. The loop filter transfer function will control the natural frequency of the loop and thus the 2BL. The third D2D takes the output of the phase controlling D2D and upconverts it to RF for phase comparison.
  • 4.2 Carrier Acquisition and Tracking
  • The D2D demodulator function requires the subharmonic LO to be coherent with the received RF carrier. If this can be achieved without a residual carrier or a pilot tone, more of the transmitted energy can be committed to the useable signal-to-noise ratio (Eb/No). FIG. 7 illustrates a block diagram of such an implementation.
  • Since D2D can translate any baseband signal to RF by appropriately modulating the carrier, D2D can be used to modify the phase or frequency of a LO output. The output of the low frequency LO is RF/m, where m is greater or equal to n. The first D2D translates RF/m to RF/n with a phase and frequency offset determined by the control voltage. The output of the first D2D is split. One signal goes to the quadrature D2D, which performs the direct to data conversion as covered in the Related UFT Patents. The second output is input to the second D2D, which translates the output to RF. At RF, another D2D (or any phase detector), is used to determine the phase error between the reference signal and the received signal.
  • The output of the phase detector is input to a logic and loop filter circuit, which generates the control voltage to adjust the phase and frequency of the reference LO output signal.
  • 4.3 Baseband Symbol Clock Recovery with D2D
  • The D2D can readily control the phase of a LO and the dPHI/dt, which is the frequency. If the LO is placed on-chip, the phase lock loop can be an on-chip analog circuit, which will use less power than a DSP solution. Analog solutions are almost always lower power solutions than DSP solutions. Based on classical phase lock loop theory, D2D implementation of the baseband clock recovery will simplify the baseband DSP and lower the power requirements of battery powered telecommunications devices requiring coherent detection schemes. The D2D embodiments described herein can be used to drastically reduce the power and weight and cost over a DSP solution.
  • In the example baseband symbol clock recovery architecture shown in FIG. 8, a D2D circuit is used in two places to perform two different functions.
  • First, the D2D circuit is used as a phase detector to compare the phase of the baseband signal on either the I or Q channel to that of the baseband clock, which will be used to sample the baseband waveforms. Second, the D2D circuit is used as a control circuit to control the frequency and phase of a baseband clock so as to track the frequency and phase of the incoming baseband signal.
  • In each of these two implementations, the D2D is configured differently. In the phase detector implementation, the two signals to be compared are input to the RF and the LO (or sampling) inputs. The output that would normally be the demodulated signal (baseband port) is a voltage proportional to the phase and frequency difference of the two signals (note that the average input power of both signals should the same). An AGC will probably be required. The output of the phase detector is low pass filtered, and the filtered voltage is used to control the second D2D. The control voltage is input to the baseband port and is used to modulate the phase and frequency of the LO. The loop filter transfer function will control the natural frequency of the loop and thus the 2BL.
  • 5. LINEAR BASEBAND TRANSVERSAL EQUALIZER D2D
  • 5.1 LMS Algorithm for Convergence
  • In the modulator configuration, shown in FIG. 9, the baseband signal will modulate (or modify) the input signal of the subharmonic port. By adjusting the voltage on the baseband port, the phase and amplitude of the signal on the subharmonic port can be controlled to create any arbitrary phase and amplitude of the signal input to the subharmonic port on the RF output port.
  • In a transversal equalizer application, the signal on the subharmonic port is at the same frequency as the signal on the RF output port. In this case, the D2D and the equalizer tap are used. For convenience, the subharmonic, baseband, and RF ports are referred to as ports A, B and C, respectively.
  • 5.2 LMS Baseband Transversal Equalizer
  • The poly-phase filter or transversal equalizer is known to persons of skill in the art. The uniqueness of this embodiment, among other features, is the use of the D2D to facilitate the implementation of the analog equalizer on a chip and as part of a system on a chip. The D2D implementation of the baseband transversal equalizer will be lower cost, lower power and lower weight and volume than the equivalent implementation in either discrete components or a DSP solution. A LMS solution can be implemented in logic (on or off chip) to control the tap weights of the equalizer by analyzing the sampled output from the A/D converters in the DSP portion of the system and minimizing the squared error. Use of D2D in this embodiment results in the benefits realized as described above. A convergence algorithm, such as a constant modulus algorithm (CMA), can be used.
  • Due to the very small size, extremely large dynamic range and signal quality, and low power consumption of the D2D, very long analog equalizers can be realized, which can be used for a wide range of channel bandwidths. If the equalizer is designed for a T/2 implementation at some symbol rate R, the equalizer can be used at any rate of R/m as long as the group delay does not exceed the time length of the entire equalizer. The T/2 will simply become T/n where n is greater than 2. The benefits of a fractional spaced equalizer will be fully realized at all data rates.
  • An example LMS implementation of a baseband linear transversal equalizer is shown in FIG. 10. B(i) are determined by some algorithm, such as LMS. The coefficients B(i) change at a very low rate (e.g., on the order of 10 to 100 Hz). If the equalizer is being used to compensate for multipath, the update must be faster than the time constant for the multipath. If “T” is less than one half of the symbol period, then the implementation shown in FIG. 10 becomes an adaptive matched filter because it is a fractional spaced equalizer.
  • Applications of the LMS implementation of the baseband transversal equalizer include: hand held communications devices and fixed systems, equalizers on satellite transponders to equalize up-link group delay, and any radio channel with linear group delay.
  • 5.3 Zero Forcing Algorithm for Convergence
  • In the modulator configuration, shown in FIG. 9, the baseband signal will modulate (or modify) the input signal of the subharmonic port. By adjusting the voltage on the baseband port, the phase and amplitude of the signal on the subharmonic port can be controlled to create any arbitrary phase and amplitude of the signal input to the subharmonic port on the RF output port.
  • In the transversal equalizer application, the signal on the subharmonic port is at the same frequency as the signal on the RF output port. In this case, the D2D and the equalizer tap are used. For convenience, the subharmonic, baseband, and RF ports are referred to as ports A, B and C, respectively.
  • 5.4 Zero Forcing Transversal Equalizer
  • The poly-phase filter or transversal equalizer is known to persons of skill in the art. The uniqueness of this embodiment, among other features, is the use of the D2D to facilitate the implementation of the analog equalizer on a chip and as part of a system on a chip. As described above, the D2D implementation of the transversal equalizer will be lower cost, lower power and lower weight and volume than the equivalent implementation in either discrete components or a DSP solution. In a zero forcing implementation of the baseband linear transversal equalizer, the sample at each time tap point is sent to a D2D correlator, which determines the correlation with the punctual signal. The output voltage of the D2D is input to a zero forcing function, and the control tap weight “B” is sent to the subject tap, which is done in parallel with all taps simultaneously, independent of modulation. Use of D2D in this application results in the benefits realized as described above.
  • Due to the very small size, extremely large dynamic range and signal quality, and low power consumption of the D2D, very long analog equalizers can be realized, which can be used for a wide range of channel bandwidths.
  • As shown in FIG. 11, if the equalizer is designed for a T/2 implementation at some symbol rate R, the equalizer can be used at any rate of R/m, as long as the group delay does not exceed the time length of the entire equalizer. The T/2 will simply be come T/n where n is greater than 2. The benefits of a fractional spaced equalizer will be fully realized at all data rates.
  • An example zero forcing implementation of the linear baseband transversal equalizer is shown in FIG. 11. B(i) are determined by some algorithm, such as LMS. The coefficients B(i) change at a very low rate (e.g., on the order of 10 to 100 Hz). If the equalizer is being used to compensate for multipath, the update must be faster than the time constant for the multipath.
  • If “T” is less than one half of the symbol period, then the implementation shown in FIG. 11 becomes an adaptive matched filter because it is a fractional spaced equalizer.
  • FIG. 12 shows a zero forcing D2D implementation of the baseband transversal equalizer.
  • Applications of the zero forcing implementation of the baseband transversal equalizer include: hand held communications devices and fixed systems, equalizers on satellite transponders to equalize up-link group delay, and any radio channel with linear group delay.
  • 6. LINEAR RF OR PASSBAND TRANSVERSAL EQUALIZER WITH D2D
  • 6.1 LMS Algorithm for Convergence
  • In the modulator configuration, shown in FIG. 9, the baseband signal will modulate (or modify) the input signal of the subharmonic port. By adjusting the voltage on the baseband port, the phase and amplitude of the signal on the subharmonic port can be controlled to create any arbitrary phase and amplitude of the signal input to the subharmonic port on the RF output port.
  • In a transversal equalizer application, the signal on the subharmonic port is at the same frequency as the signal on the RF output port. In this case, the D2D and the equalizer tap are used. For convenience, the subharmonic, baseband, and RF ports are referred to as ports A, B and C, respectively.
  • 6.2 LMS RF or Passband Transversal Equalizer
  • The poly-phase filter or transversal equalizer is known to persons of skill in the art. The uniqueness of this embodiment, among other features, is the use of the D2D to facilitate the implementation of the analog equalizer on a chip and as part of a system on a chip. As described above, the D2D implementation of the transversal equalizer will be lower cost, lower power and lower weight and volume than the equivalent implementation in either discrete components or a DSP solution. A LMS solution can be implemented in logic (on or off chip), which would control the tap weights of the equalizer by analyzing the sampled output from the A/D converters in the DSP portion of the system and minimizing the squared error. Use of D2D in this embodiment results in the benefits realized as described above. A convergence algorithm, such as a CMA, can be used.
  • This equalizer is implemented at RF or passband and only one delay line equalizer is required since D2D control taps can adjust the tap outputs from zero to maximum amplitude and from 0 to 360 degrees.
  • Due to the very small size, extremely large dynamic range and signal quality, and low power consumption of the D2D, very long analog equalizers can be realized which can be used for a wide range of channel bandwidths. If the equalizer is designed for a T/2 implementation at some symbol rate R, the equalizer can be used at any rate of R/m as long as the group delay does not exceed the time length of the entire equalizer. The T/2 will simply be come T/n where n is greater than 2. The benefits of a fractional spaced equalizer will be fully realized at all data rates.
  • An example LMS implementation of a RF or passband linear transversal equalizer is shown in FIG. 13. B(i) are determined by some algorithm, such as LMS. The coefficients B(i) change at a very low rate (e.g., on the order of 10 to 100 Hz). If the equalizer is being used to compensate for multipath, the update must be faster than the time constant for the multipath. If “T” is less than one half of the symbol period, then the implementation shown in FIG. 13 becomes an adaptive matched filter because it is a fractional spaced equalizer.
  • Applications of the LMS implementation of the RF or passband linear transversal equalizer include: hand held communications devices and fixed systems, equalizers on satellite transponders to equalize up-link group delay, and any radio channel with linear group delay.
  • 6.3 Zero Forcing Algorithm for Convergence
  • In the modulator configuration, shown in FIG. 9, the baseband signal will modulate (or modify) the input signal of the subharmonic port. By adjusting the voltage on the baseband port, the phase and amplitude of the signal on the subharmonic port can be controlled to create any arbitrary phase and amplitude of the signal input to the subharmonic port on the RF output port.
  • In a transversal equalizer application, the signal on the subharmonic port is at the same frequency as the signal on the RF output port. In this case, the D2D and the equalizer tap can be used. For convenience, the subharmonic, baseband, and RF ports are referred to as ports A, B and C, respectively.
  • 6.4 Zero Forcing RF or Passband Transversal Equalizer
  • The poly-phase filter or transversal equalizer is known to persons of skill in the art. The uniqueness of this embodiment, among other features, is the use of the D2D to facilitate the implementation of the analog equalizer on a chip and as part of a system on a chip. The D2D implementation of the transversal equalizer will be lower cost, lower power and lower weight and volume than the equivalent implementation in either discrete components or a DSP solution. In a zero forcing implementation of the RF or passband linear transversal equalizer, the sample at each time tap point is sent to a D2D correlator, which determines the correlation with the punctual signal. The output voltage of the D2D is input to a zero forcing function, and the control tap weight “B” is sent to the subject tap, which is done in parallel with all taps simultaneously, independent of modulation. Use of D2D in this embodiment results in the benefits realized as described above.
  • This equalizer is implemented at RF or passband and only one delay line equalizer is required since D2D control taps can adjust the tap outputs from zero to maximum amplitude and from 0 to 360 degrees.
  • Due to the very small size, extremely large dynamic range and signal quality, and low power consumption of the D2D, very long analog equalizers can be realized which can be used for a wide range of channel bandwidths. If the equalizer is designed for a T/2 implementation at some symbol rate R, the equalizer can be used at any rate of R/m as long as the group delay does not exceed the time length of the entire equalizer. The T/2 will simply be come T/n where n is greater than 2. The benefits of a fractional spaced equalizer will be fully realized at all data rates.
  • An example zero forcing implementation of an RF or passband linear transversal equalizer is shown in FIG. 14. B(i) are determined by some algorithm, such as LMS. The coefficients B(i) change at a very low rate (e.g., on the order of 10 to 100 Hz). If the equalizer is being used to compensate for multipath, the update must be faster than the time constant for the multipath. If “T” is less than one half of the symbol period, then the implementation shown in FIG. 14 becomes an adaptive matched filter because it is a fractional spaced equalizer.
  • FIG. 15 shows an example zero forcing D2D implementation of the RF or passband transversal equalizer.
  • 7. D2D AS A SPREADER/DESPREADER
  • Since D2D transmission/reception is symmetric, we need only describe a spreader/transmitter. FIG. 16 illustrates a block diagram of an example D2D spreader/transmitter.
  • 7.1 Case 1
  • If signal {tilde over (s)}(t) is fixed and a local oscillator (LO) contains BPSK or QPSK symbols with spreading information, then
      • bpsk(i)=PSK symbol in ith bit interval, and
      • bpsk(i)=e i , where φi is one of the allowed phases (e.g., for BPSK, φi=+π/2 or φi=−π/2).
  • FIG. 17 shows a binary waveform σ(t) that has the same out of phases as bpsk. Also shown in FIG. 17 is a spread waveform. An example implementation of Case 1 is shown in FIG. 18. In FIG. 18, the LO signal is data modulated and spread.
  • 7.2 Case 2
  • In this case, {tilde over (s)}(t) is modulated using any type of modulation and spreading, and the LO is unmodulated. If {tilde over (s)}(t) is any information signal (i.e., analog, digital, etc.) and σ is any spreading sequence (note that while σ is normally binary, σ can include frequency shifts, such as hopping spread spectrum, wavelets, etc.), then Case 2 may be implemented as shown in FIG. 19.
  • 7.3 Case 3
  • In this case, {tilde over (s)}(t) is an arbitrary baseband signal and the LO is binary modulated. Case 3 may be implemented as shown in FIG. 20.
  • 7.4 Case 4 p In this case, {tilde over (s)}(t) is an arbitrary baseband signal and a reference signal is binary and/or frequency modulated. Case 4 may be implemented as shown in FIG. 21.
  • 7.5 Case 5
  • In this case, a reference signal is frequency step controlled and is used in conjunction with binary spreading. Case 5 may be implemented as shown in FIG. 22.
  • 8. EXAMPLE IMPLEMENTATIONS OF GATED TRANSFER UNIT
  • Another embodiment of the present invention is implemented as a combination of the following embodiments: (1) D2D in linear transversal equalizers for pre and post equalizers (transmit and receive), including linear baseband with LMS or CMA algorithm, linear RF/passband with LMS or CMA algorithm, linear baseband with zero forcing circuits, and linear RF/passband with zero forcing circuits; (2) carrier acquisition and tracking loop with D2D; (3) baseband clock recovery loop with D2D; (4) use of D2D as a correlator; (5) use of D2D as a phase detector; (6) use of D2D as a modulator; (7) use of D2D as a demodulator; (8) use of D2D as a phase control in a phase locked loop; (9) use of D2D as an up-converter; and (10) use of D2D as a down-converter.
  • As shown in FIG. 23, this embodiment allows an entire modem to be implemented with D2D circuits. The functions usually done in DSP can be done in analog and combined in a single chip or on a chip with the DSP to drastically cut the power consumption for functions (1)-(10) listed above. This embodiment will eliminate a great deal of DSP processing requirements, thus reducing power consumption.
  • 9. CONCLUSION
  • Example implementations of the methods, systems and components of the invention have been described herein. As noted elsewhere, these example implementations have been described for illustrative purposes only, and are not limiting. Other implementation embodiments are possible and covered by the invention, such as but not limited to software and software/hardware implementations of the systems and components of the invention. Such implementation embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein.
  • While various application embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments.

Claims (1)

1. A circuit, comprising:
a switch that sub-samples and transfers energy from a first signal; and
a storage device, coupled to said switch, that stores said transferred energy, wherein a second signal is generated from said first signal, and wherein a frequency of said second signal differs from a frequency of said first signal.
US11/292,118 1999-04-16 2005-12-02 Methods and systems for utilizing universal frequency translators for phase and/or frequency detection Abandoned US20060083329A1 (en)

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US12983999P true 1999-04-16 1999-04-16
US15804799P true 1999-10-07 1999-10-07
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US17150299P true 1999-12-22 1999-12-22
US17149699P true 1999-12-22 1999-12-22
US17738100P true 2000-01-24 2000-01-24
US17770500P true 2000-01-24 2000-01-24
US17770200P true 2000-01-24 2000-01-24
US18066700P true 2000-02-07 2000-02-07
US09/525,615 US6853690B1 (en) 1999-04-16 2000-03-14 Method, system and apparatus for balanced frequency up-conversion of a baseband signal and 4-phase receiver and transceiver embodiments
US11/015,653 US7773688B2 (en) 1999-04-16 2004-12-20 Method, system, and apparatus for balanced frequency up-conversion, including circuitry to directly couple the outputs of multiple transistors
US11/292,118 US20060083329A1 (en) 1999-04-16 2005-12-02 Methods and systems for utilizing universal frequency translators for phase and/or frequency detection

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US11/292,118 Abandoned US20060083329A1 (en) 1999-04-16 2005-12-02 Methods and systems for utilizing universal frequency translators for phase and/or frequency detection
US12/823,055 Active US8077797B2 (en) 1999-04-16 2010-06-24 Method, system, and apparatus for balanced frequency up-conversion of a baseband signal
US13/323,550 Active US8571135B2 (en) 1999-04-16 2011-12-12 Method, system and apparatus for balanced frequency up-conversion of a baseband signal
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140270029A1 (en) * 2013-03-14 2014-09-18 Research & Business Foundation Sungkyunkwan University Apparatus and method for supporting device to device communication

Families Citing this family (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8406724B2 (en) 1998-10-21 2013-03-26 Parkervision, Inc. Applications of universal frequency translation
US7236754B2 (en) 1999-08-23 2007-06-26 Parkervision, Inc. Method and system for frequency up-conversion
US6813485B2 (en) * 1998-10-21 2004-11-02 Parkervision, Inc. Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same
US7515896B1 (en) 1998-10-21 2009-04-07 Parkervision, Inc. Method and system for down-converting an electromagnetic signal, and transforms for same, and aperture relationships
US7039372B1 (en) 1998-10-21 2006-05-02 Parkervision, Inc. Method and system for frequency up-conversion with modulation embodiments
US6061551A (en) 1998-10-21 2000-05-09 Parkervision, Inc. Method and system for down-converting electromagnetic signals
US6370371B1 (en) 1998-10-21 2002-04-09 Parkervision, Inc. Applications of universal frequency translation
US7010286B2 (en) 2000-04-14 2006-03-07 Parkervision, Inc. Apparatus, system, and method for down-converting and up-converting electromagnetic signals
US7110444B1 (en) 1999-08-04 2006-09-19 Parkervision, Inc. Wireless local area network (WLAN) using universal frequency translation technology including multi-phase embodiments and circuit implementations
US6853690B1 (en) * 1999-04-16 2005-02-08 Parkervision, Inc. Method, system and apparatus for balanced frequency up-conversion of a baseband signal and 4-phase receiver and transceiver embodiments
US6879817B1 (en) * 1999-04-16 2005-04-12 Parkervision, Inc. DC offset, re-radiation, and I/Q solutions using universal frequency translation technology
US7693230B2 (en) 1999-04-16 2010-04-06 Parkervision, Inc. Apparatus and method of differential IQ frequency up-conversion
US8295406B1 (en) 1999-08-04 2012-10-23 Parkervision, Inc. Universal platform module for a plurality of communication protocols
US7065162B1 (en) 1999-04-16 2006-06-20 Parkervision, Inc. Method and system for down-converting an electromagnetic signal, and transforms for same
US7454453B2 (en) 2000-11-14 2008-11-18 Parkervision, Inc. Methods, systems, and computer program products for parallel correlation and applications thereof
US7072427B2 (en) * 2001-11-09 2006-07-04 Parkervision, Inc. Method and apparatus for reducing DC offsets in a communication system
US7085335B2 (en) * 2001-11-09 2006-08-01 Parkervision, Inc. Method and apparatus for reducing DC offsets in a communication system
US7058139B2 (en) * 2001-11-16 2006-06-06 Koninklijke Philips Electronics N.V. Transmitter with transmitter chain phase adjustment on the basis of pre-stored phase information
KR100459545B1 (en) * 2002-04-19 2004-12-04 삼성전자주식회사 Apparatus for transmitting of radio signal in mobile terminal and controlling method thereof
US6975848B2 (en) * 2002-06-04 2005-12-13 Parkervision, Inc. Method and apparatus for DC offset removal in a radio frequency communication channel
US7321640B2 (en) * 2002-06-07 2008-01-22 Parkervision, Inc. Active polyphase inverter filter for quadrature signal generation
US7460584B2 (en) 2002-07-18 2008-12-02 Parkervision, Inc. Networking methods and systems
US7379883B2 (en) 2002-07-18 2008-05-27 Parkervision, Inc. Networking methods and systems
KR20050012479A (en) * 2003-07-25 2005-02-02 유티스타콤코리아 유한회사 Cdma signal generator for using awgn and saw filter
WO2005015775A1 (en) * 2003-08-11 2005-02-17 Nortel Networks Limited System and method for embedding ofdm in cdma systems
US7443924B2 (en) * 2003-09-30 2008-10-28 Viasat, Inc. Residual carrier and side band processing system and method
TWI280017B (en) * 2005-10-03 2007-04-21 Ind Tech Res Inst Communication system with demodulation of two-level differential amplitude-shift-keying signals and method thereof
US8041327B2 (en) * 2006-03-16 2011-10-18 Newport Media, Inc. Wideband resistive input mixer with noise-cancelled impedance
US20080014873A1 (en) * 2006-07-12 2008-01-17 Krayer Yvonne L Methods and apparatus for adaptive local oscillator nulling
CN101529820B (en) * 2006-11-03 2013-06-19 索尤若驱动有限及两合公司 Method and device for bus arbitration, converter and manufacturing installation
US20080219391A1 (en) * 2007-03-07 2008-09-11 Texas Instruments Incorporated Systems and Methods for Distributing a Clock Signal
US8630332B2 (en) * 2007-05-10 2014-01-14 Qualcomm Incorporated GNSS signal processor
US8792590B2 (en) * 2009-02-25 2014-07-29 Harris Corporation Communications device with in-phase/quadrature (I/Q) DC offset, gain and phase imbalance compensation and related method
US8391781B2 (en) * 2009-09-15 2013-03-05 Miteq, Inc Measuring satellite linearity from earth using a low duty cycle pulsed microwave signal
EP2478732A4 (en) * 2009-09-15 2017-07-26 Miteq, Inc. A method of transmitting higher power from a satellite by more efficiently using the existing satellite power amplifiers
JP5395634B2 (en) * 2009-11-18 2014-01-22 ルネサスエレクトロニクス株式会社 Quadrature modulator and a semiconductor integrated circuit incorporating it
US8798216B2 (en) * 2010-01-05 2014-08-05 Maxlinear, Inc. High dynamic range radio architecture with enhanced image rejection
US8892184B2 (en) 2010-10-18 2014-11-18 Siemens Medical Solutions Usa, Inc. Systems and methods for reducing interference in a dual modality imaging system
JP5881492B2 (en) * 2012-03-23 2016-03-09 株式会社東芝 Ask signal generator
US8965290B2 (en) * 2012-03-29 2015-02-24 General Electric Company Amplitude enhanced frequency modulation
US8837636B2 (en) * 2012-08-31 2014-09-16 Motorola Solutions, Inc. Method and apparatus for out-of-channel emission suppression
US9055594B2 (en) * 2013-06-07 2015-06-09 Intel IP Corporation Reducing transmission signal artifact spacing
US9300336B2 (en) 2013-08-01 2016-03-29 Harris Corporation Direct conversion receiver device with first and second stages and related methods

Citations (99)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270385A (en) * 1938-10-10 1942-01-20 Hartford Nat Bank & Trust Co Multicarrier transmission system
US2462069A (en) * 1942-05-07 1949-02-22 Int Standard Electric Corp Radio communication system
US2462181A (en) * 1944-09-28 1949-02-22 Western Electric Co Radio transmitting system
US2497859A (en) * 1947-11-19 1950-02-21 Western Union Telegraph Co Frequency diversity telegraph system
US2499279A (en) * 1947-04-22 1950-02-28 Ericsson Telefon Ab L M Single side band modulator
US3023309A (en) * 1960-12-19 1962-02-27 Bell Telephone Labor Inc Communication system
US3118117A (en) * 1959-10-30 1964-01-14 Int Standard Electric Corp Modulators for carrier communication systems
US3555428A (en) * 1966-10-03 1971-01-12 Xerox Corp Fsk receiver for detecting a data signal with the same number of cycles of each carrier frequency
US3643168A (en) * 1969-07-07 1972-02-15 Standard Kallsman Ind Inc Solid-state tuned uhf television tuner
US3714577A (en) * 1971-05-06 1973-01-30 W Hayes Single sideband am-fm modulation system
US3716730A (en) * 1971-04-19 1973-02-13 Motorola Inc Intermodulation rejection capabilities of field-effect transistor radio frequency amplifiers and mixers
US3717844A (en) * 1969-04-03 1973-02-20 Inst Francais Du Petrole Process of high reliability for communications between a master installation and secondary installations and device for carrying out this process
US3868601A (en) * 1973-06-18 1975-02-25 Us Navy Digital single-sideband modulator
US3940697A (en) * 1974-12-02 1976-02-24 Hy-Gain Electronics Corporation Multiple band scanning radio
US4003002A (en) * 1974-09-12 1977-01-11 U.S. Philips Corporation Modulation and filtering device
US4066841A (en) * 1974-01-25 1978-01-03 Serck Industries Limited Data transmitting systems
US4066919A (en) * 1976-04-01 1978-01-03 Motorola, Inc. Sample and hold circuit
US4132952A (en) * 1975-11-11 1979-01-02 Sony Corporation Multi-band tuner with fixed broadband input filters
US4142155A (en) * 1976-05-19 1979-02-27 Nippon Telegraph And Telephone Public Corporation Diversity system
US4245355A (en) * 1979-08-08 1981-01-13 Eaton Corporation Microwave frequency converter
US4250458A (en) * 1979-05-31 1981-02-10 Digital Communications Corporation Baseband DC offset detector and control circuit for DC coupled digital demodulator
US4253066A (en) * 1980-05-13 1981-02-24 Fisher Charles B Synchronous detection with sampling
US4253069A (en) * 1978-03-31 1981-02-24 Siemens Aktiengesellschaft Filter circuit having a biquadratic transfer function
US4253067A (en) * 1978-12-11 1981-02-24 Rockwell International Corporation Baseband differentially phase encoded radio signal detector
US4313222A (en) * 1979-05-25 1982-01-26 Blaupunkt Werke Gmbh H-F Portion of TV receiver
US4369522A (en) * 1978-07-03 1983-01-18 Motorola, Inc. Singly-balanced active mixer circuit
US4370572A (en) * 1980-01-17 1983-01-25 Trw Inc. Differential sample-and-hold circuit
US4430629A (en) * 1980-04-25 1984-02-07 Siemens Aktiengesellschaft Electrical filter circuit operated with a definite sampling and clock frequency fT which consists of CTD elements
US4563773A (en) * 1984-03-12 1986-01-07 The United States Of America As Represented By The Secretary Of The Army Monolithic planar doped barrier subharmonic mixer
US4634998A (en) * 1985-07-17 1987-01-06 Hughes Aircraft Company Fast phase-lock frequency synthesizer with variable sampling efficiency
US4718113A (en) * 1985-05-08 1988-01-05 Alcatel Nv Zero-IF receiver wih feedback loop for suppressing interfering signals
US4726041A (en) * 1985-07-03 1988-02-16 Siemens Aktiengesellschaft Digital filter switch for data receiver
US4801823A (en) * 1986-09-10 1989-01-31 Nippon Gakki Seizo Kabushiki Kaisha Sample hold circuit
US4806790A (en) * 1987-02-16 1989-02-21 Nec Corporation Sample-and-hold circuit
US4893316A (en) * 1985-04-04 1990-01-09 Motorola, Inc. Digital radio frequency receiver
US4893341A (en) * 1989-08-01 1990-01-09 At&E Corporation Digital receiver operating at sub-nyquist sampling rate
US4894766A (en) * 1988-11-25 1990-01-16 Hazeltine Corporation Power supply frequency converter
US4896152A (en) * 1989-03-02 1990-01-23 General Electric Company Telemetry system with a sending station using recursive filter for bandwidth limiting
US4902979A (en) * 1989-03-10 1990-02-20 General Electric Company Homodyne down-converter with digital Hilbert transform filtering
US4982353A (en) * 1989-09-28 1991-01-01 General Electric Company Subsampling time-domain digital filter using sparsely clocked output latch
US4984077A (en) * 1988-12-28 1991-01-08 Victor Company Of Japan, Ltd. Signal converting apparatus
US4995055A (en) * 1988-06-16 1991-02-19 Hughes Aircraft Company Time shared very small aperture satellite terminals
US5083050A (en) * 1990-11-30 1992-01-21 Grumman Aerospace Corporation Modified cascode mixer circuit
US5091921A (en) * 1989-04-20 1992-02-25 Nec Corporation Direct conversion receiver with dithering local carrier frequency for detecting transmitted carrier frequency
US5179731A (en) * 1989-06-09 1993-01-12 Licentia-Patent-Verwaltungs-Gmbh Frequency conversion circuit
US5278826A (en) * 1991-04-11 1994-01-11 Usa Digital Radio Method and apparatus for digital audio broadcasting and reception
US5282023A (en) * 1992-05-14 1994-01-25 Hitachi America, Ltd. Apparatus for NTSC signal interference cancellation through the use of digital recursive notch filters
US5282222A (en) * 1992-03-31 1994-01-25 Michel Fattouche Method and apparatus for multiple access between transceivers in wireless communications using OFDM spread spectrum
US5287516A (en) * 1991-01-10 1994-02-15 Landis & Gyr Betriebs Ag Demodulation process for binary data
US5379141A (en) * 1989-12-04 1995-01-03 Scientific-Atlanta, Inc. Method and apparatus for transmitting broadband amplitude modulated radio frequency signals over optical links
US5379040A (en) * 1992-02-17 1995-01-03 Nec Corporation Digital-to-analog converter
US5388063A (en) * 1992-11-18 1995-02-07 Yozan Inc. Filter circuit with switchable finite impulse response and infinite impulse response filter characteristics
US5389839A (en) * 1993-03-03 1995-02-14 Motorola, Inc. Integratable DC blocking circuit
US5390215A (en) * 1992-10-13 1995-02-14 Hughes Aircraft Company Multi-processor demodulator for digital cellular base station employing partitioned demodulation procedure with pipelined execution
US5390364A (en) * 1992-11-02 1995-02-14 Harris Corporation Least-mean squares adaptive digital filter havings variable size loop bandwidth
US5481570A (en) * 1993-10-20 1996-01-02 At&T Corp. Block radio and adaptive arrays for wireless systems
US5483549A (en) * 1994-03-04 1996-01-09 Stanford Telecommunications, Inc. Receiver having for charge-coupled-device based receiver signal processing
US5483691A (en) * 1992-06-08 1996-01-09 Motorola, Inc. Zero intermediate frequency receiver having an automatic gain control circuit
US5483600A (en) * 1994-02-14 1996-01-09 Aphex Systems, Ltd. Wave dependent compressor
US5483695A (en) * 1993-05-12 1996-01-09 Csem Centre Suisse D'electronique Et De Microtechnique Intermediate frequency FM receiver using analog oversampling to increase signal bandwidth
US5483193A (en) * 1995-03-24 1996-01-09 Ford Motor Company Circuit for demodulating FSK signals
US5483245A (en) * 1992-08-26 1996-01-09 Kollmorgen Artus ILS signal analysis device and method
US5490176A (en) * 1991-10-21 1996-02-06 Societe Anonyme Dite: Alcatel Telspace Detecting false-locking and coherent digital demodulation using the same
US5490173A (en) * 1993-07-02 1996-02-06 Ford Motor Company Multi-stage digital RF translator
US5493581A (en) * 1992-08-14 1996-02-20 Harris Corporation Digital down converter and method
US5493721A (en) * 1992-11-07 1996-02-20 Grundig E.M.V. Receiver for a digital radio signal
US5495202A (en) * 1993-06-30 1996-02-27 Hughes Aircraft Company High spectral purity digital waveform synthesizer
US5495200A (en) * 1993-04-06 1996-02-27 Analog Devices, Inc. Double sampled biquad switched capacitor filter
US5495500A (en) * 1994-08-09 1996-02-27 Intermec Corporation Homodyne radio architecture for direct sequence spread spectrum data reception
US5592131A (en) * 1993-06-17 1997-01-07 Canadian Space Agency System and method for modulating a carrier frequency
US5600680A (en) * 1993-06-01 1997-02-04 Matsushita Electric Industrial Co., Ltd. High frequency receiving apparatus
US5602847A (en) * 1995-09-27 1997-02-11 Lucent Technologies Inc. Segregated spectrum RF downconverter for digitization systems
US5602868A (en) * 1993-02-17 1997-02-11 Motorola, Inc. Multiple-modulation communication system
US5604732A (en) * 1993-12-31 1997-02-18 Samsung Electronics Co., Ltd. Up-link access apparatus in direct sequence code division multiple access system
US5604592A (en) * 1994-09-19 1997-02-18 Textron Defense Systems, Division Of Avco Corporation Laser ultrasonics-based material analysis system and method using matched filter processing
US5705949A (en) * 1996-09-13 1998-01-06 U.S. Robotics Access Corp. Compensation method for I/Q channel imbalance errors
US5705955A (en) * 1995-12-21 1998-01-06 Motorola, Inc. Frequency locked-loop using a microcontroller as a comparator
US5710992A (en) * 1996-07-12 1998-01-20 Uniden America Corporation Chain search in a scanning receiver
US5710998A (en) * 1995-12-19 1998-01-20 Motorola, Inc. Method and apparatus for improved zero intermediate frequency receiver latency
US5859878A (en) * 1995-08-31 1999-01-12 Northrop Grumman Corporation Common receive module for a programmable digital radio
US5864754A (en) * 1996-02-05 1999-01-26 Hotto; Robert System and method for radio signal reconstruction using signal processor
US6011435A (en) * 1996-06-12 2000-01-04 Fujitsu Limited Transmission-line loss equalizing circuit
US6014551A (en) * 1996-07-18 2000-01-11 Nokia Mobile Phones Ltd. Arrangement for transmitting and receiving radio frequency signal at two frequency bands
US6014176A (en) * 1995-06-21 2000-01-11 Sony Corporation Automatic phase control apparatus for phase locking the chroma burst of analog and digital video data using a numerically controlled oscillator
US6018553A (en) * 1996-09-18 2000-01-25 Wireless Access Multi-level mixer architecture for direct conversion of FSK signals
US6018262A (en) * 1994-09-30 2000-01-25 Yamaha Corporation CMOS differential amplifier for a delta sigma modulator applicable for an analog-to-digital converter
US6169733B1 (en) * 1997-05-12 2001-01-02 Northern Telecom Limited Multiple mode capable radio receiver device
US6175728B1 (en) * 1997-03-05 2001-01-16 Nec Corporation Direct conversion receiver capable of canceling DC offset voltages
US6178319B1 (en) * 1997-09-26 2001-01-23 Matsushita Electric Industrial Co., Ltd. Microwave mixing circuit and down-converter
US6182011B1 (en) * 1996-04-01 2001-01-30 The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration Method and apparatus for determining position using global positioning satellites
US6335656B1 (en) * 1999-09-30 2002-01-01 Analog Devices, Inc. Direct conversion receivers and filters adapted for use therein
US6509777B2 (en) * 2001-01-23 2003-01-21 Resonext Communications, Inc. Method and apparatus for reducing DC offset
US6512785B1 (en) * 1998-02-12 2003-01-28 Yozan Inc. Matched filter bank
US6512798B1 (en) * 1998-03-06 2003-01-28 Hitachi Denshi Kabushiki Kaisha Digital communication system of orthogonal modulation type
US6512544B1 (en) * 1998-06-17 2003-01-28 Foveon, Inc. Storage pixel sensor and array with compression
US20060002491A1 (en) * 2000-11-27 2006-01-05 Broadcom Corporation IF FSK receiver
US7321751B2 (en) * 1999-04-16 2008-01-22 Parkervision, Inc. Method and apparatus for improving dynamic range in a communication system
US7321735B1 (en) * 1998-10-21 2008-01-22 Parkervision, Inc. Optical down-converter using universal frequency translation technology
US7321640B2 (en) * 2002-06-07 2008-01-22 Parkervision, Inc. Active polyphase inverter filter for quadrature signal generation

Family Cites Families (760)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2057613A (en) 1932-07-28 1936-10-13 Gen Electric Diversity factor receiving system
US2241078A (en) 1937-11-01 1941-05-06 Frederick K Vreeland Multiplex communication
US2283575A (en) 1938-04-19 1942-05-19 Rca Corp High frequency transmission system
GB556208A (en) 1941-04-25 1943-09-24 Standard Telephones Cables Ltd Arrangement for conversion of frequency modulation to phase modulation and the application thereof to the production of a frequency modulated wave from a frequency stable oscillator
US2410350A (en) 1943-02-06 1946-10-29 Standard Telephones Cables Ltd Method and means for communication
US2472798A (en) 1943-11-29 1949-06-14 Rca Corp Low-pass filter system
US2451430A (en) 1946-04-23 1948-10-12 Jefferson Standard Broadcastin Carrier frequency shift signaling
BE473802A (en) 1946-08-20
US2802208A (en) 1952-06-25 1957-08-06 Charles F Hobbs Radio frequency multiplexing
US2985875A (en) 1958-02-12 1961-05-23 Marconi Wireless Telegraph Co Radio communication systems
US3069679A (en) 1959-04-22 1962-12-18 Westinghouse Electric Corp Multiplex communication systems
US3246084A (en) 1960-08-26 1966-04-12 Bolt Beranek & Newman Method of and apparatus for speech compression and the like
US3114106A (en) 1960-11-23 1963-12-10 Mcmauus Robert Paul Frequency diversity system
US3104393A (en) 1961-10-18 1963-09-17 Joseph H Vogelman Method and apparatus for phase and amplitude control in ionospheric communications systems
US3226643A (en) 1962-01-08 1965-12-28 Avco Corp Command communication system of the rectangular wave type
US3258694A (en) 1964-01-03 1966-06-28 Multi-channel p.m. transmitter with automatic modulation index control
US3384822A (en) 1964-03-21 1968-05-21 Nippon Electric Co Frequency-shift-keying phase-modulation code transmission system
US3383598A (en) 1965-02-15 1968-05-14 Space General Corp Transmitter for multiplexed phase modulated singaling system
DE1936252U (en) 1965-05-11 1966-04-07 Vdo Schindling Temperaturfuehler.
FR1504609A (en) 1966-09-21 1967-12-08 Ibm France data transmission system
US3454718A (en) 1966-10-03 1969-07-08 Xerox Corp Fsk transmitter with transmission of the same number of cycles of each carrier frequency
US3617892A (en) 1967-02-27 1971-11-02 Rca Corp Frequency modulation system for spreading radiated power
NL6706736A (en) 1967-05-13 1968-11-14 Philips Nv
CH497089A (en) 1968-07-26 1970-09-30 Autophon Ag System for the transmission of continuous signals
US3629696A (en) 1968-08-06 1971-12-21 Northeast Electronics Corp Method and apparatus for measuring delay distortion including simultaneously applied modulated signals
US3614627A (en) 1968-10-15 1971-10-19 Data Control Systems Inc Universal demodulation system
US3548342A (en) 1968-10-15 1970-12-15 Ibm Digitally controlled amplitude modulation circuit
US3614630A (en) 1969-02-04 1971-10-19 Develco Radio frequency standard and voltage controlled oscillator
US3626417A (en) 1969-03-07 1971-12-07 Everett A Gilbert Hybrid frequency shift-amplitude modulated tone system
US3617898A (en) 1969-04-09 1971-11-02 Eugene A Janning Jr Orthogonal passive frequency converter with control port and signal port
US3767984A (en) 1969-09-03 1973-10-23 Nippon Electric Co Schottky barrier type field effect transistor
US3623160A (en) 1969-09-17 1971-11-23 Sanders Associates Inc Data modulator employing sinusoidal synthesis
DE1962156A1 (en) 1969-12-11 1971-02-11
US6531979B1 (en) 1970-02-10 2003-03-11 The United States Of America As Represented By The Secretary Of The Navy Adaptive time-compression stabilizer
US3626315A (en) 1970-04-07 1971-12-07 Sperry Rand Corp Voltage-controlled oscillator selectively injection locked to stable frequency harmonics
US4004237A (en) * 1970-05-01 1977-01-18 Harris Corporation System for communication and navigation
US3641442A (en) 1970-06-25 1972-02-08 Hughes Aircraft Co Digital frequency synthesizer
US3621402A (en) 1970-08-03 1971-11-16 Bell Telephone Labor Inc Sampled data filter
US3689841A (en) 1970-10-23 1972-09-05 Signatron Communication system for eliminating time delay effects when used in a multipath transmission medium
US3702440A (en) 1970-11-16 1972-11-07 Motorola Inc Selective calling system providing an increased number of calling codes or auxiliary information transfer
US3662268A (en) 1970-11-17 1972-05-09 Bell Telephone Labor Inc Diversity communication system using distinct spectral arrangements for each branch
US3694754A (en) 1970-12-28 1972-09-26 Tracor Suppression of electrostatic noise in antenna systems
US3735048A (en) 1971-05-28 1973-05-22 Motorola Inc In-band data transmission system
US3719903A (en) * 1971-06-25 1973-03-06 Bell Telephone Labor Inc Double sideband modem with either suppressed or transmitted carrier
US3736513A (en) 1971-06-28 1973-05-29 Warwick Electronics Inc Receiver tuning system
US3809821A (en) 1971-10-08 1974-05-07 W Melvin Three-channel data modem apparatus
US3740636A (en) 1971-11-05 1973-06-19 Us Navy Charge regulator and monitor for spacecraft solar cell/battery system control
US3806811A (en) * 1972-01-20 1974-04-23 Gte Sylvania Inc Multiple carrier phase modulated signal generating apparatus
US3764921A (en) 1972-10-27 1973-10-09 Control Data Corp Sample and hold circuit
US3991277A (en) 1973-02-15 1976-11-09 Yoshimutsu Hirata Frequency division multiplex system using comb filters
US3852530A (en) 1973-03-19 1974-12-03 M Shen Single stage power amplifiers for multiple signal channels
FR2245130B1 (en) 1973-09-21 1977-03-11 Jaeger
US3949300A (en) * 1974-07-03 1976-04-06 Sadler William S Emergency radio frequency warning device
JPS5113208U (en) 1974-07-17 1976-01-30
US3967202A (en) 1974-07-25 1976-06-29 Northern Illinois Gas Company Data transmission system including an RF transponder for generating a broad spectrum of intelligence bearing sidebands
US4035732A (en) 1974-10-03 1977-07-12 The United States Of America As Represented By The Secretary Of The Army High dynamic range receiver front end mixer requiring low local oscillator injection power
US3980945A (en) 1974-10-07 1976-09-14 Raytheon Company Digital communications system with immunity to frequency selective fading
US3987280A (en) 1975-05-21 1976-10-19 The United States Of America As Represented By The Secretary Of The Navy Digital-to-bandpass converter
US4017798A (en) 1975-09-08 1977-04-12 Ncr Corporation Spread spectrum demodulator
US4047121A (en) 1975-10-16 1977-09-06 The United States Of America As Represented By The Secretary Of The Navy RF signal generator
US4013966A (en) * 1975-10-16 1977-03-22 The United States Of America As Represented By The Secretary Of The Navy Fm rf signal generator using step recovery diode
US4019140A (en) * 1975-10-24 1977-04-19 Bell Telephone Laboratories, Incorporated Methods and apparatus for reducing intelligible crosstalk in single sideband radio systems
US4045740A (en) 1975-10-28 1977-08-30 The United States Of America As Represented By The Secretary Of The Army Method for optimizing the bandwidth of a radio receiver
US4020487A (en) 1975-10-31 1977-04-26 Fairchild Camera And Instrument Corporation Analog-to-digital converter employing common mode rejection circuit
JPS5826699B2 (en) 1975-11-13 1983-06-04 Sony Corp
US4032847A (en) 1976-01-05 1977-06-28 Raytheon Company Distortion adapter receiver having intersymbol interference correction
US4048598A (en) 1976-05-28 1977-09-13 Rca Corporation Uhf tuning circuit utilizing a varactor diode
NL175575C (en) 1976-05-28 1984-11-16 Philips Nv Filter and demodulation device.
US4081748A (en) * 1976-07-01 1978-03-28 Northern Illinois Gas Company Frequency/space diversity data transmission system
US4080573A (en) 1976-07-16 1978-03-21 Motorola, Inc. Balanced mixer using complementary devices
US4051475A (en) 1976-07-21 1977-09-27 The United States Ofamerica As Represented By The Secretary Of The Army Radio receiver isolation system
JPS5914939B2 (en) 1976-09-30 1984-04-06 Nippon Electric Co
JPS5731811B2 (en) 1977-05-16 1982-07-07
US4145659A (en) * 1977-05-25 1979-03-20 General Electric Company UHF electronic tuner
US4130765A (en) 1977-05-31 1978-12-19 Rafi Arakelian Low supply voltage frequency multiplier with common base transistor amplifier
US4173164A (en) 1977-06-01 1979-11-06 Nippon Gakki Seizo Kabushiki Kaisha Electronic musical instrument with frequency modulation of a tone signal with an audible frequency signal
US4346477A (en) 1977-08-01 1982-08-24 E-Systems, Inc. Phase locked sampling radio receiver
JPS6145433B2 (en) 1977-10-27 1986-10-08 Sony Corp
US4170764A (en) 1978-03-06 1979-10-09 Bell Telephone Laboratories, Incorporated Amplitude and frequency modulation system
US4204171A (en) 1978-05-30 1980-05-20 Rca Corporation Filter which tracks changing frequency of input signal
US4241451A (en) 1978-06-26 1980-12-23 Rockwell International Corporation Single sideband signal demodulator
US4210872A (en) 1978-09-08 1980-07-01 American Microsystems, Inc. High pass switched capacitor filter section
US4308614A (en) 1978-10-26 1981-12-29 Fisher Charles B Noise-reduction sampling system
JPS56500198A (en) 1979-01-29 1981-02-19
US4389579A (en) 1979-02-13 1983-06-21 Motorola, Inc. Sample and hold circuit
US4409877A (en) 1979-06-11 1983-10-18 Cbs, Inc. Electronic tone generating system
US4320361A (en) * 1979-07-20 1982-03-16 Marconi Instruments Limited Amplitude and frequency modulators using a switchable component controlled by data signals
US4484143A (en) 1982-05-17 1984-11-20 Rockwell International Corporation CCD Demodulator circuit
US4320536A (en) * 1979-09-18 1982-03-16 Dietrich James L Subharmonic pumped mixer circuit
JPS6211826B2 (en) 1979-09-28 1987-03-14 Nippon Electric Co
FR2471081B1 (en) 1979-11-30 1986-05-30 Thomson Csf SC filter charge transfer
US4286283A (en) 1979-12-20 1981-08-25 Rca Corporation Transcoder
US4356558A (en) 1979-12-20 1982-10-26 Martin Marietta Corporation Optimum second order digital filter
FR2473808A1 (en) 1980-01-11 1981-07-17 Thomson Csf Subharmonic mixer for millimeter wave receiver and receiver using such a mixer
FR2474791B1 (en) 1980-01-29 1982-11-26 Thomson Csf
DE3007907C2 (en) 1980-03-01 1988-04-21 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt, De
US4485347A (en) 1980-09-04 1984-11-27 Mitsubishi Denki Kabushiki Kaisha Digital FSK demodulator
US4393352A (en) 1980-09-18 1983-07-12 The Perkin-Elmer Corporation Sample-and-hold hybrid active RC filter
US4472785A (en) 1980-10-13 1984-09-18 Victor Company Of Japan, Ltd. Sampling frequency converter
US4334324A (en) 1980-10-31 1982-06-08 Rca Corporation Complementary symmetry FET frequency converter circuits
US4517519A (en) 1980-11-07 1985-05-14 Kabushiki Kaisha Suwa Seikosha FSK Demodulator employing a switched capacitor filter and period counters
US4360867A (en) 1980-12-08 1982-11-23 Bell Telephone Laboratories, Incorporated Broadband frequency multiplication by multitransition operation of step recovery diode
DE3047386C2 (en) 1980-12-16 1989-05-11 Philips Patentverwaltung Gmbh, 2000 Hamburg, De
US4363976A (en) 1981-01-19 1982-12-14 Rockwell International Corporation Subinterval sampler
US4393395A (en) 1981-01-26 1983-07-12 Rca Corporation Balanced modulator with feedback stabilization of carrier balance
CA1170354A (en) 1981-02-18 1984-07-03 Takao Mogi Aft circuit
GB2094079A (en) 1981-02-20 1982-09-08 Philips Electronic Associated Fm demodulator
US4384357A (en) 1981-04-03 1983-05-17 Canadian Patens & Development Limited Self-synchronization circuit for a FFSK or MSK demodulator
US4380828A (en) 1981-05-26 1983-04-19 Zenith Radio Corporation UHF MOSFET Mixer
DE3121146C2 (en) 1981-05-27 1988-09-08 Siemens Ag, 1000 Berlin Und 8000 Muenchen, De
US4481642A (en) 1981-06-02 1984-11-06 Texas Instruments Incorporated Integrated circuit FSK modem
US4483017A (en) 1981-07-31 1984-11-13 Rca Corporation Pattern recognition system using switched capacitors
US4517520A (en) 1981-08-24 1985-05-14 Trio Kabushiki Kaisha Circuit for converting a staircase waveform into a smoothed analog signal
GB2106359B (en) 1981-09-24 1985-07-03 Standard Telephones Cables Ltd Direct conversion radio receiver for fm signals
FR2515449B1 (en) 1981-10-23 1986-08-14 Thomson Csf Subharmonic mixer device Microwave and microwave system using such a device
US4446438A (en) 1981-10-26 1984-05-01 Gte Automatic Electric Incorporated Switched capacitor n-path filter
JPS58105493A (en) 1981-12-16 1983-06-23 Matsushita Electric Ind Co Ltd Storing and holding device for amplitude of pulse signal
US4441080A (en) 1981-12-17 1984-04-03 Bell Telephone Laboratories, Incorporated Amplifier with controlled gain
US4456990A (en) 1982-02-10 1984-06-26 Fisher Charles B Periodic wave elimination by negative feedback
FR2521784B1 (en) 1982-02-12 1985-09-20 Thomson Csf Mixer has transistor for hyperfrequences
US4479226A (en) 1982-03-29 1984-10-23 At&T Bell Laboratories Frequency-hopped single sideband mobile radio system
US4481490A (en) 1982-06-07 1984-11-06 Ael Microtel, Ltd. Modulator utilizing high and low frequency carriers
US4510467A (en) 1982-06-28 1985-04-09 Gte Communication Systems Corporation Switched capacitor DSB modulator/demodulator
US4504803A (en) 1982-06-28 1985-03-12 Gte Lenkurt, Incorporated Switched capacitor AM modulator/demodulator
US4463320A (en) 1982-07-06 1984-07-31 Rockwell International Corporation Automatic gain control circuit
US4510453A (en) 1982-07-13 1985-04-09 Westinghouse Electric Corp. Frequency modulation or pulse modulation demodulator
US4470145A (en) 1982-07-26 1984-09-04 Hughes Aircraft Company Single sideband quadricorrelator
WO1985004750A1 (en) * 1982-11-26 1985-10-24 Mitsubishi Denki Kabushiki Kaisha Analog input circuit
JPH0110007Y2 (en) 1983-01-28 1989-03-22
GB2141007B (en) * 1983-06-02 1986-07-23 Standard Telephones Cables Ltd Demodulator logic for frequency shift keyed signals
US4616191A (en) 1983-07-05 1986-10-07 Raytheon Company Multifrequency microwave source
NL8302482A (en) 1983-07-12 1985-02-01 Philips Nv Band-rejection filter of the switched capacities type.
US4663744A (en) 1983-08-31 1987-05-05 Terra Marine Engineering, Inc. Real time seismic telemetry system
US4591930A (en) 1983-09-23 1986-05-27 Eastman Kodak Company Signal processing for high resolution electronic still camera
GB2149244B (en) * 1983-10-29 1987-01-21 Standard Telephones Cables Ltd Digital demodulator arrangement for quadrature signals
FR2554994B1 (en) 1983-11-15 1989-05-26 Thomson Csf Device for generation of a fractional frequency of a reference frequency
JPH0793553B2 (en) 1983-11-18 1995-10-09 株式会社日立製作所 Switched capacitor filter
US4660164A (en) 1983-12-05 1987-04-21 The United States Of America As Represented By The Secretary Of The Navy Multiplexed digital correlator
US4577157A (en) * 1983-12-12 1986-03-18 International Telephone And Telegraph Corporation Zero IF receiver AM/FM/PM demodulator using sampling techniques
US4562414A (en) 1983-12-27 1985-12-31 Motorola, Inc. Digital frequency modulation system and method
JPH0354904B2 (en) 1983-12-28 1991-08-21
US4970703A (en) 1984-05-10 1990-11-13 Magnavox Government And Industrial Electronics Company Switched capacitor waveform processing circuit
US4601046A (en) 1984-05-15 1986-07-15 Halpern Peter H System for transmitting data through a troposcatter medium
GB2161344A (en) 1984-07-06 1986-01-08 Philips Electronic Associated Transmission of digital data
JPS6160515U (en) 1984-08-22 1986-04-23
US4603300A (en) 1984-09-21 1986-07-29 General Electric Company Frequency modulation detector using digital signal vector processing
US4621217A (en) 1984-09-21 1986-11-04 Tektronix, Inc. Anti-aliasing filter circuit for oscilloscopes
US4596046A (en) 1984-10-01 1986-06-17 Motorola, Inc. Split loop AFC system for a SSB receiver
CH666584A5 (en) 1984-11-22 1988-07-29 Zellweger Uster Ag Method and apparatus for demodulating high frequency modulated signals by means of digital filters and demodulators digital, as well as application of the method in a fernsteuerempfaenger.
US4716388A (en) 1984-12-24 1987-12-29 Jacobs Gordon M Multiple output allpass switched capacitor filters
US4651210A (en) * 1984-12-24 1987-03-17 Rca Corporation Adjustable gamma controller
US4716376A (en) 1985-01-31 1987-12-29 At&T Information Systems Inc. Adaptive FSK demodulator and threshold detector
IN166145B (en) 1985-03-04 1990-03-17 Dymax Corp "bandwidth ultrasound transceiver"
JPH0347766B2 (en) * 1985-04-26 1991-07-22 Tokyo Shibaura Electric Co
US4612518A (en) 1985-05-28 1986-09-16 At&T Bell Laboratories QPSK modulator or demodulator using subharmonic pump carrier signals
US4833445A (en) 1985-06-07 1989-05-23 Sequence Incorporated Fiso sampling system
GB2177273A (en) 1985-06-26 1987-01-14 Philips Electronic Associated R f power amplifier
GB2177876A (en) 1985-07-08 1987-01-28 Philips Electronic Associated Radio system and a transmitter and a receiver for use in the system
US4810904A (en) * 1985-07-17 1989-03-07 Hughes Aircraft Company Sample-and-hold phase detector circuit
US4785463A (en) 1985-09-03 1988-11-15 Motorola, Inc. Digital global positioning system receiver
US4675882A (en) 1985-09-10 1987-06-23 Motorola, Inc. FM demodulator
GB2181914B (en) * 1985-10-22 1989-09-20 Plessey Co Plc Frequency doubling oscillator and heterodyne circuit incorporating same
US5345239A (en) 1985-11-12 1994-09-06 Systron Donner Corporation High speed serrodyne digital frequency translator
US4653117A (en) 1985-11-18 1987-03-24 Motorola, Inc. Dual conversion FM receiver using phase locked direct conversion IF
CA1244139A (en) 1985-12-11 1988-11-01 Larry J. Conway Microwave waveform receiver
US4648021A (en) * 1986-01-03 1987-03-03 Motorola, Inc. Frequency doubler circuit and method
US4740675A (en) 1986-04-10 1988-04-26 Hewlett-Packard Company Digital bar code slot reader with threshold comparison of the differentiated bar code signal
US4751468A (en) 1986-05-01 1988-06-14 Tektronix, Inc. Tracking sample and hold phase detector
US4733403A (en) * 1986-05-12 1988-03-22 Motorola, Inc. Digital zero IF selectivity section
JPS62264728A (en) 1986-05-12 1987-11-17 Minolta Camera Co Ltd Analog-digital converter
IT1204401B (en) 1986-06-20 1989-03-01 Sgs Microelettronica Spa A filtering device bandpass sampled data
US4757538A (en) 1986-07-07 1988-07-12 Tektronix, Inc. Separation of L+R from L-R in BTSC system
US4791600A (en) 1986-07-28 1988-12-13 Tektronix, Inc. Digital pipelined heterodyne circuit
US4688253A (en) 1986-07-28 1987-08-18 Tektronix, Inc. L+R separation system
US4740792A (en) 1986-08-27 1988-04-26 Hughes Aircraft Company Vehicle location system
US4745463A (en) 1986-09-25 1988-05-17 Rca Licensing Corporation Generalized chrominance signal demodulator for a sampled data television signal processing system
US4791584A (en) 1986-10-15 1988-12-13 Eastman Kodak Company Sub-nyquist interferometry
NL8603110A (en) 1986-12-08 1988-07-01 Philips Nv A circuit for the recovery of a carrier wave.
US4811422A (en) 1986-12-22 1989-03-07 Kahn Leonard R Reduction of undesired harmonic components
US5014304A (en) 1987-01-09 1991-05-07 Sgs-Thomson Microelectronics S.R.L. Method of reconstructing an analog signal, particularly in digital telephony applications, and a circuit device implementing the method
GB2201559A (en) 1987-01-23 1988-09-01 Gen Electric Plc Electrical signal mixer circuit
US4737969A (en) * 1987-01-28 1988-04-12 Motorola, Inc. Spectrally efficient digital modulation method and apparatus
JPS63215185A (en) 1987-03-03 1988-09-07 Matsushita Electric Ind Co Ltd Sub-nyquist coding device and decoding device
FR2612018B1 (en) 1987-03-06 1989-05-26 Labo Electronique Physique Mixer hyperfrequences
US4871987A (en) 1987-03-28 1989-10-03 Kabushiki Kaisha Kenwood FSK or am modulator with digital waveform shaping
US4761798A (en) 1987-04-02 1988-08-02 Itt Aerospace Optical Baseband phase modulator apparatus employing digital techniques
US4816704A (en) 1987-04-21 1989-03-28 Fiori David Frequency-to-voltage converter
US4789837A (en) 1987-04-22 1988-12-06 Sangamo Weston, Inc. Switched capacitor mixer/multiplier
FR2615675B1 (en) 1987-05-21 1989-06-30 Alcatel Espace modules signals digitally demodulating method and device for implementing such a method
US4855894A (en) 1987-05-25 1989-08-08 Kabushiki Kaisha Kenwood Frequency converting apparatus
US4910752A (en) * 1987-06-15 1990-03-20 Motorola, Inc. Low power digital receiver
US4811362A (en) * 1987-06-15 1989-03-07 Motorola, Inc. Low power digital receiver
US4772853A (en) 1987-08-12 1988-09-20 Rockwell International Corporation Digital delay FM demodulator with filtered noise dither
US4862121A (en) 1987-08-13 1989-08-29 Texas Instruments Incorporated Switched capacitor filter
GB8719849D0 (en) 1987-08-21 1987-09-30 British Telecomm Fsk discriminator
FR2619973B1 (en) * 1987-08-26 1990-01-05 France Etat A sampled switched capacitor filter
EP0305775B1 (en) 1987-08-29 1994-01-26 Fujitsu Limited FSK demodulation circuit
GB2209442A (en) * 1987-09-04 1989-05-10 Marconi Instruments Ltd Frequency synthesizer
US4841265A (en) 1987-09-25 1989-06-20 Nec Corporation Surface acoustic wave filter
US5020149A (en) 1987-09-30 1991-05-28 Conifer Corporation Integrated down converter and interdigital filter apparatus and method for construction thereof
HU212136B (en) 1987-10-27 1996-03-28 Cedcom Network Systems Pty Ltd Communication system
US4922452A (en) 1987-11-16 1990-05-01 Analytek, Ltd. 10 Gigasample/sec two-stage analog storage integrated circuit for transient digitizing and imaging oscillography
US4814649A (en) 1987-12-18 1989-03-21 Rockwell International Corporation Dual gate FET mixing apparatus with feedback means
USRE35494E (en) 1987-12-22 1997-04-22 Sgs-Thomson Microelectronics, S.R.L. Integrated active low-pass filter of the first order
US4857928A (en) 1988-01-28 1989-08-15 Motorola, Inc. Method and arrangement for a sigma delta converter for bandpass signals
US4819252A (en) * 1988-02-16 1989-04-04 Thomson Consumer Electronics, Inc. Sampled data subsampling apparatus
GB2215545A (en) 1988-03-16 1989-09-20 Philips Electronic Associated A direct-conversion receiver
NL8800696A (en) 1988-03-21 1989-10-16 Philips Nv Sampling system, pulse generation circuit and sampling circuit suitable for use in a sampling system, and oscilloscope equipped with a sampling system.
US4885671A (en) 1988-03-24 1989-12-05 General Electric Company Pulse-by-pulse current mode controlled power supply
GB2215945A (en) 1988-03-26 1989-09-27 Stc Plc Digital direct conversion radio
GB2219899A (en) 1988-06-17 1989-12-20 Philips Electronic Associated A zero if receiver
FR2633467B1 (en) 1988-06-24 1990-08-24 Thomson Csf frequency multiplier rank of programmable multiplication
US4944025A (en) 1988-08-09 1990-07-24 At&E Corporation Direct conversion FM receiver with offset
GB2222488A (en) 1988-08-31 1990-03-07 Philips Electronic Associated Broad bandwidth planar power combiner/divider device
ES2045047T3 (en) 1988-08-31 1994-01-16 Siemens Ag Four-quadrant multiplier of multiple entries.
SE463540B (en) 1988-09-19 1990-12-03 Ericsson Telefon Ab L M Saett foer to digitize a radio communication system arbitrary radio signals and means of foer utoevande Sættet
US5062122A (en) 1988-09-28 1991-10-29 Kenwood Corporation Delay-locked loop circuit in spread spectrum receiver
US5220583A (en) 1988-10-03 1993-06-15 Motorola, Inc. Digital fm demodulator with a reduced sampling rate
US4972436A (en) 1988-10-14 1990-11-20 Hayes Microcomputer Products, Inc. High performance sigma delta based analog modem front end
US4943974A (en) 1988-10-21 1990-07-24 Geostar Corporation Detection of burst signal transmissions
US5016242A (en) 1988-11-01 1991-05-14 Gte Laboratories Incorporated Microwave subcarrier generation for fiber optic systems
US4873492A (en) 1988-12-05 1989-10-10 American Telephone And Telegraph Company, At&T Bell Laboratories Amplifier with modulated resistor gain control
GB2225910A (en) 1988-12-08 1990-06-13 Philips Electronic Associated Processing sampled analogue electrical signals
FR2640829B1 (en) 1988-12-20 1991-02-08 Thomson Hybrides Microondes Device for direct modulation or demodulation in hyperfrequences
US4885587A (en) 1988-12-22 1989-12-05 Westinghouse Electric Corp. Multibit decorrelated spur digital radio frequency memory
US5058107A (en) 1989-01-05 1991-10-15 Hughes Aircraft Company Efficient digital frequency division multiplexed signal receiver
US5251218A (en) 1989-01-05 1993-10-05 Hughes Aircraft Company Efficient digital frequency division multiplexed signal receiver
US4890162A (en) 1989-01-26 1989-12-26 Rca Licensing Corporation Adjustable antialias filters
US5006854A (en) 1989-02-13 1991-04-09 Silicon Systems, Inc. Method and apparatus for converting A/D nonlinearities to random noise
US4888557A (en) 1989-04-10 1989-12-19 General Electric Company Digital subharmonic sampling down-converter
AT118938T (en) 1989-04-20 1995-03-15 Siemens Ag Transmission link.
FR2646741B1 (en) 1989-05-03 1994-09-02 Thomson Hybrides Microondes The blocking sampler has high frequency sampling
US4931716A (en) 1989-05-05 1990-06-05 Milan Jovanovic Constant frequency zero-voltage-switching multi-resonant converter
US4931921A (en) 1989-05-30 1990-06-05 Motorola, Inc. Wide bandwidth frequency doubler
US5157687A (en) 1989-06-29 1992-10-20 Symbol Technologies, Inc. Packet data communication network
DE3925329A1 (en) 1989-07-31 1991-02-07 Siemens Ag A circuit arrangement for controlling the amplitude of video signals
US4992736A (en) 1989-08-04 1991-02-12 General Electric Company Radio frequency receiver for a NMR instrument
US5170414A (en) 1989-09-12 1992-12-08 Siemens Pacesetter, Inc. Adjustable output level signal transmitter
US4955079A (en) 1989-09-29 1990-09-04 Raytheon Company Waveguide excited enhancement and inherent rejection of interference in a subharmonic mixer
US5015963A (en) 1989-09-29 1991-05-14 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Synchronous demodulator
US5012245A (en) 1989-10-04 1991-04-30 At&T Bell Laboratories Integral switched capacitor FIR filter/digital-to-analog converter for sigma-delta encoded digital audio
JPH03132185A (en) 1989-10-17 1991-06-05 Sanyo Electric Co Ltd Television signal converter
US5003621A (en) * 1989-11-02 1991-03-26 Motorola, Inc. Direct conversion FM receiver
US5005169A (en) 1989-11-16 1991-04-02 Westinghouse Electric Corp. Frequency division multiplex guardband communication system for sending information over the guardbands
JPH03160803A (en) 1989-11-20 1991-07-10 Pioneer Electron Corp Balanced mixer circuit
US5063387A (en) 1989-11-20 1991-11-05 Unisys Corporation Doppler frequency compensation circuit
US5006810A (en) 1989-12-14 1991-04-09 Northern Telecom Limited Second order active filters
US5020745A (en) 1989-12-20 1991-06-04 General Electric Company Reaction wheel fricton compensation using dither
US5023572A (en) 1989-12-20 1991-06-11 Westinghouse Electric Corp. Voltage-controlled oscillator with rapid tuning loop and method for tuning same
US5239496A (en) 1989-12-27 1993-08-24 Nynex Science & Technology, Inc. Digital parallel correlator
GB2240240A (en) 1990-01-19 1991-07-24 Philips Electronic Associated Radio receiver for direct sequence spread spectrum signals
JPH063861B2 (en) 1990-02-14 1994-01-12 株式会社東芝 Active filters
US5263194A (en) 1990-03-07 1993-11-16 Seiko Corp. Zero if radio receiver for intermittent operation
US5230097A (en) 1990-03-09 1993-07-20 Scientific-Atlanta, Inc. Offset frequency converter for phase/amplitude data measurement receivers
US5113094A (en) 1990-03-13 1992-05-12 Wiltron Company Method and apparatus for increasing the high frequency sensitivity response of a sampler frequency converter
US5095536A (en) 1990-03-23 1992-03-10 Rockwell International Corporation Direct conversion receiver with tri-phase architecture
US5095533A (en) 1990-03-23 1992-03-10 Rockwell International Corporation Automatic gain control system for a direct conversion receiver
JPH043540A (en) 1990-04-19 1992-01-08 Yamaha Corp Spread spectrum communication equipment
GB9010637D0 (en) 1990-05-11 1990-07-04 Secr Defence A high frequency multichannel diversity differential phase shift(dpsk)communications system
US5033110A (en) 1990-05-18 1991-07-16 Northern Telecom Limited Frequency converter for a radio communications system
US5047860A (en) 1990-06-01 1991-09-10 Gary Rogalski Wireless audio and video signal transmitter and receiver system apparatus
US5010585A (en) 1990-06-01 1991-04-23 Garcia Rafael A Digital data and analog radio frequency transmitter
JP2927896B2 (en) * 1990-06-28 1999-07-28 日本電気株式会社 Spectrum suppression circuit
JP2679889B2 (en) 1990-07-19 1997-11-19 株式会社テック Reception control method for a radio communication apparatus and the device
JP2817373B2 (en) 1990-07-30 1998-10-30 松下電器産業株式会社 Direct conversion receiver
GB9017418D0 (en) 1990-08-08 1990-09-19 Gen Electric Co Plc Half frequency mixer
USRE35829E (en) 1990-08-27 1998-06-23 Axonn Corporation Binary phase shift keying modulation system and/or frequency multiplier
US5214787A (en) 1990-08-31 1993-05-25 Karkota Jr Frank P Multiple audio channel broadcast system
US5126682A (en) 1990-10-16 1992-06-30 Stanford Telecommunications, Inc. Demodulation method and apparatus incorporating charge coupled devices
KR960000775B1 (en) * 1990-10-19 1996-01-12 세끼모또 타다히로 Output level control circuit for high freq power amp
KR920010383B1 (en) 1990-10-23 1992-11-27 강진구 Homodyne tv receiver
US5222079A (en) 1990-10-25 1993-06-22 Motorola, Inc. Adaptive information signal receiver
JP2801389B2 (en) 1990-11-02 1998-09-21 キヤノン株式会社 Signal processing device
JPH04177946A (en) 1990-11-09 1992-06-25 Sony Corp Digital demodulator
NL9002489A (en) 1990-11-15 1992-06-01 Philips Nv Receiver.
US5263196A (en) 1990-11-19 1993-11-16 Motorola, Inc. Method and apparatus for compensation of imbalance in zero-if downconverters
FR2669787A1 (en) 1990-11-23 1992-05-29 Alcatel Telspace Symmetric UHF mixer
US5140699A (en) 1990-12-24 1992-08-18 American Nucleonics Corporation Detector DC offset compensator
US5136267A (en) 1990-12-26 1992-08-04 Audio Precision, Inc. Tunable bandpass filter system and filtering method
US5220680A (en) 1991-01-15 1993-06-15 Pactel Corporation Frequency signal generator apparatus and method for simulating interference in mobile communication systems
JP2850160B2 (en) 1991-01-25 1999-01-27 松下電器産業株式会社 Time division duplex radio transceiver device
US5212827A (en) 1991-02-04 1993-05-18 Motorola, Inc. Zero intermediate frequency noise blanker
US5249203A (en) 1991-02-25 1993-09-28 Rockwell International Corporation Phase and gain error control system for use in an i/q direct conversion receiver
JP2749456B2 (en) 1991-03-06 1998-05-13 三菱電機株式会社 Wireless communication device
US5150124A (en) 1991-03-25 1992-09-22 Motorola, Inc. Bandpass filter demodulation for FM-CW systems
US5444865A (en) 1991-04-01 1995-08-22 Motorola, Inc. Generating transmit injection from receiver first and second injections
US5315583A (en) 1991-04-11 1994-05-24 Usa Digital Radio Method and apparatus for digital audio broadcasting and reception
US5131014A (en) 1991-04-19 1992-07-14 General Instrument Corporation Apparatus and method for recovery of multiphase modulated data
US5239686A (en) 1991-04-29 1993-08-24 Echelon Corporation Transceiver with rapid mode switching capability
US5682099A (en) 1994-03-14 1997-10-28 Baker Hughes Incorporated Method and apparatus for signal bandpass sampling in measurement-while-drilling applications
GB9109617D0 (en) 1991-05-03 1991-06-26 Texas Instruments Ltd Method and apparatus for signal processing
US5239687A (en) 1991-05-06 1993-08-24 Chen Shih Chung Wireless intercom having a transceiver in which a bias current for the condenser microphone and the driving current for the speaker are used to charge a battery during transmission and reception, respectively
AU1918892A (en) 1991-05-10 1992-12-30 Echelon Corporation Power line communication while avoiding determinable interference harmonics
US5355114A (en) 1991-05-10 1994-10-11 Echelon Corporation Reconstruction of signals using redundant channels
US5790587A (en) 1991-05-13 1998-08-04 Omnipoint Corporation Multi-band, multi-mode spread-spectrum communication system
US5337014A (en) 1991-06-21 1994-08-09 Harris Corporation Phase noise measurements utilizing a frequency down conversion/multiplier, direct spectrum measurement technique
US5260970A (en) 1991-06-27 1993-11-09 Hewlett-Packard Company Protocol analyzer pod for the ISDN U-interface
JPH05102899A (en) 1991-08-16 1993-04-23 Shiyoudenriyoku Kosoku Tsushin Kenkyusho:Kk Multi-frequency communication system
US5252865A (en) 1991-08-22 1993-10-12 Triquint Semiconductor, Inc. Integrating phase detector
US5151661A (en) 1991-08-26 1992-09-29 Westinghouse Electric Corp. Direct digital FM waveform generator for radar systems
FR2681994B1 (en) 1991-09-26 1994-09-30 Alcatel Telspace A digital transmission receiver comprising a coherent demodulation is carried out directly by microwaves.
US5218562A (en) 1991-09-30 1993-06-08 American Neuralogix, Inc. Hamming data correlator having selectable word-length
JP2800500B2 (en) 1991-10-01 1998-09-21 松下電器産業株式会社 Burst transmission power control circuit
US5307517A (en) 1991-10-17 1994-04-26 Rich David A Adaptive notch filter for FM interference cancellation
US5222144A (en) 1991-10-28 1993-06-22 Ford Motor Company Digital quadrature radio receiver with two-step processing
US5204642A (en) 1991-10-31 1993-04-20 Advanced Micro Devices, Inc. Frequency controlled recursive oscillator having sinusoidal output
JP2897795B2 (en) 1991-10-31 1999-05-31 日本電気株式会社 Sample-and-hold type phase comparator circuit
US5263198A (en) 1991-11-05 1993-11-16 Honeywell Inc. Resonant loop resistive FET mixer
IT1252132B (en) 1991-11-27 1995-06-05 Sits Soc It Telecom Siemens Multiplier radiofrequency frequency comprising an automatic level control circuit
DE4241882A1 (en) 1991-12-13 1993-06-17 Clarion Co Ltd
JPH05168041A (en) 1991-12-16 1993-07-02 Sony Corp Video signal recorder
JPH05183456A (en) 1991-12-27 1993-07-23 Nec Corp Control signal generator
US5172019A (en) 1992-01-17 1992-12-15 Burr-Brown Corporation Bootstrapped FET sampling switch
JPH05259745A (en) 1992-03-11 1993-10-08 Sumitomo Electric Ind Ltd Mixer circuit
US5222250A (en) 1992-04-03 1993-06-22 Cleveland John F Single sideband radio signal processing system
US5535402A (en) 1992-04-30 1996-07-09 The United States Of America As Represented By The Secretary Of The Navy System for (N•M)-bit correlation using N M-bit correlators
US5410541A (en) 1992-05-04 1995-04-25 Ivon International, Inc. System for simultaneous analog and digital communications over an analog channel
JPH05315608A (en) 1992-05-13 1993-11-26 Tadahiro Omi Semiconductor device
US5325204A (en) 1992-05-14 1994-06-28 Hitachi America, Ltd. Narrowband interference cancellation through the use of digital recursive notch filters
US5400084A (en) 1992-05-14 1995-03-21 Hitachi America, Ltd. Method and apparatus for NTSC signal interference cancellation using recursive digital notch filters
JP3166321B2 (en) 1992-07-01 2001-05-14 日本電気株式会社 Modulated signal transmission system
US5592415A (en) 1992-07-06 1997-01-07 Hitachi, Ltd. Non-volatile semiconductor memory
US5465071A (en) 1992-07-13 1995-11-07 Canon Kabushiki Kaisha Information signal processing apparatus
US5465415A (en) 1992-08-06 1995-11-07 National Semiconductor Corporation Even order term mixer
WO1994005087A1 (en) 1992-08-25 1994-03-03 Wireless Access, Inc. A direct conversion receiver for multiple protocols
WO1994006206A1 (en) 1992-08-27 1994-03-17 Motorola Inc. Push pull buffer with noise cancelling symmetry
US5471162A (en) 1992-09-08 1995-11-28 The Regents Of The University Of California High speed transient sampler
JPH0690225A (en) 1992-09-09 1994-03-29 Shodenryoku Kosoku Tsushin Kenkyusho:Kk Diversity radio receiver
US5339395A (en) 1992-09-17 1994-08-16 Delco Electronics Corporation Interface circuit for interfacing a peripheral device with a microprocessor operating in either a synchronous or an asynchronous mode
FR2696598B1 (en) 1992-10-01 1994-11-04 Sgs Thomson Microelectronics A voltage booster circuit of the charge pump type with bootstrapped oscillator.
US5594470A (en) 1992-10-02 1997-01-14 Teletransaction, Inc. Highly integrated portable electronic work slate unit
US5428640A (en) 1992-10-22 1995-06-27 Digital Equipment Corporation Switch circuit for setting and signaling a voltage level
TW225067B (en) 1992-11-26 1994-06-11 Philips Electronics Nv
DE69329140D1 (en) 1992-11-26 2000-09-07 Koninkl Philips Electronics Nv A direct conversion
US5339459A (en) 1992-12-03 1994-08-16 Motorola, Inc. High speed sample and hold circuit and radio constructed therewith
DE69427378D1 (en) 1993-01-08 2001-07-05 Sony Corp Monolithic microwave integrated circuit
JP3025384B2 (en) 1993-01-13 2000-03-27 シャープ株式会社 Digital fm demodulator
US5661424A (en) 1993-01-27 1997-08-26 Gte Laboratories Incorporated Frequency hopping synthesizer using dual gate amplifiers
JP3400003B2 (en) * 1993-02-18 2003-04-28 株式会社日立国際電気 Complex modulation and demodulation system
GB2308514B (en) 1993-03-01 1997-09-17 Texas Instruments Ltd A digital oscillator
CA2132026C (en) 1993-03-04 2007-10-30 Per Anders Lennart Stein Modular radio communications system
FR2702903B1 (en) 1993-03-17 1995-05-24 Europ Agence Spatiale radiofrequency signal receiver.
CA2156430C (en) 1993-03-31 2000-03-21 Ian Christopher Smith Generation of optical signals with rf components
US5523760A (en) 1993-04-12 1996-06-04 The Regents Of The University Of California Ultra-wideband receiver
US5392460A (en) 1993-04-23 1995-02-21 Nokia Mobile Phones Ltd. Dual mode radiotelephone terminal selectively operable for frequency modulated or phase modulated operation
US5465418A (en) 1993-04-29 1995-11-07 Drexel University Self-oscillating mixer circuits and methods therefor
US5369404A (en) 1993-04-30 1994-11-29 The Regents Of The University Of California Combined angle demodulator and digitizer
US5479447A (en) 1993-05-03 1995-12-26 The Board Of Trustees Of The Leland Stanford, Junior University Method and apparatus for adaptive, variable bandwidth, high-speed data transmission of a multicarrier signal over digital subscriber lines
US5375146A (en) 1993-05-06 1994-12-20 Comsat Corporation Digital frequency conversion and tuning scheme for microwave radio receivers and transmitters
US5400363A (en) 1993-05-07 1995-03-21 Loral Aerospace Corp. Quadrature compensation for orthogonal signal channels
US5438329A (en) 1993-06-04 1995-08-01 M & Fc Holding Company, Inc. Duplex bi-directional multi-mode remote instrument reading and telemetry system
US5410743A (en) 1993-06-14 1995-04-25 Motorola, Inc. Active image separation mixer
JPH08501428A (en) 1993-06-21 1996-02-13 モトローラ・インコーポレイテッド Apparatus and method for frequency conversion in a communication device
US5423082A (en) 1993-06-24 1995-06-06 Motorola, Inc. Method for a transmitter to compensate for varying loading without an isolator
CA2125468C (en) 1993-06-28 1998-04-21 Danny Thomas Pinckley Method of selectively reducing spectral components in a wideband radio frequency signal
US5559468A (en) 1993-06-28 1996-09-24 Motorola, Inc. Feedback loop closure in a linear transmitter
US5347280A (en) 1993-07-02 1994-09-13 Texas Instruments Deutschland Gmbh Frequency diversity transponder arrangement
GB9313981D0 (en) 1993-07-06 1993-08-18 Plessey Semiconductors Ltd Wide-band microwave modulator arrangements
JP3189508B2 (en) 1993-07-08 2001-07-16 株式会社村田製作所 Surface acoustic wave filter
JP3139225B2 (en) 1993-07-08 2001-02-26 株式会社村田製作所 Surface acoustic wave filter
US5949471A (en) 1993-07-29 1999-09-07 Gemstar Development Corporation Apparatus and method for improved parental control of television use
US5428638A (en) 1993-08-05 1995-06-27 Wireless Access Inc. Method and apparatus for reducing power consumption in digital communications devices
US5440311A (en) 1993-08-06 1995-08-08 Martin Marietta Corporation Complementary-sequence pulse radar with matched filtering and Doppler tolerant sidelobe suppression preceding Doppler filtering
FI107855B (en) 1993-09-10 2001-10-15 Nokia Mobile Phones Ltd Acting signal demodulation sigma-delta converter
US5617451A (en) 1993-09-13 1997-04-01 Matsushita Electric Industrial Co., Ltd. Direct-conversion receiver for digital-modulation signal with signal strength detection
GB2282030B (en) 1993-09-14 1997-09-24 Plessey Semiconductors Ltd Direct conversion receiver
US5454007A (en) 1993-09-24 1995-09-26 Rockwell International Corporation Arrangement for and method of concurrent quadrature downconversion input sampling of a bandpass signal
US5434546A (en) 1993-11-15 1995-07-18 Palmer; James K. Circuit for simultaneous amplitude modulation of a number of signals
US5539770A (en) 1993-11-19 1996-07-23 Victor Company Of Japan, Ltd. Spread spectrum modulating apparatus using either PSK or FSK primary modulation
US5422909A (en) 1993-11-30 1995-06-06 Motorola, Inc. Method and apparatus for multi-phase component downconversion
GB9326464D0 (en) 1993-12-24 1994-02-23 Philips Electronics Uk Ltd Receiver having an adjustable bandwidth filter
JP2638462B2 (en) 1993-12-29 1997-08-06 日本電気株式会社 Semiconductor device
US5461646A (en) 1993-12-29 1995-10-24 Tcsi Corporation Synchronization apparatus for a diversity receiver
US5454009A (en) 1994-01-13 1995-09-26 Scientific-Atlanta, Inc. Method and apparatus for providing energy dispersal using frequency diversity in a satellite communications system
US5574755A (en) 1994-01-25 1996-11-12 Philips Electronics North America Corporation I/Q quadraphase modulator circuit
US5463356A (en) 1994-01-28 1995-10-31 Palmer; James K. FM band multiple signal modulator
DE69522245T2 (en) 1994-01-31 2002-05-16 Hitachi Electronics Television camera with a digital video signal processing circuit
US5446421A (en) 1994-02-02 1995-08-29 Thomson Consumer Electronics, Inc. Local oscillator phase noise cancelling modulation technique
US5410270A (en) 1994-02-14 1995-04-25 Motorola, Inc. Differential amplifier circuit having offset cancellation and method therefor
US5552789A (en) 1994-02-14 1996-09-03 Texas Instruments Deutschland Gmbh Integrated vehicle communications system
US5523719A (en) 1994-02-15 1996-06-04 Rockwell International Corporation Component insensitive, analog bandpass filter
US5809060A (en) 1994-02-17 1998-09-15 Micrilor, Inc. High-data-rate wireless local-area network
GB2286950B (en) 1994-02-22 1998-06-17 Roke Manor Research A direct conversion receiver
US5557641A (en) 1994-03-04 1996-09-17 Stanford Telecommunications, Inc. Charge-coupled-device based transmitters and receivers
PL187110B1 (en) 1994-03-31 2004-05-31 The Arbitron Company Method of activating multi frequency code- for sound signal
TW257917B (en) 1994-04-12 1995-09-21 Philips Electronics Nv Receiver comprising a pulse count FM demodulator, and pulse count FM demodulator
US5412352A (en) 1994-04-18 1995-05-02 Stanford Telecommunications, Inc. Modulator having direct digital synthesis for broadband RF transmission
EP0683571B1 (en) 1994-05-16 2003-07-23 SANYO ELECTRIC Co., Ltd. Diversity reception device
US5416449A (en) 1994-05-23 1995-05-16 Synergy Microwave Corporation Modulator with harmonic mixers
US5564097A (en) 1994-05-26 1996-10-08 Rockwell International Spread intermediate frequency radio receiver with adaptive spurious rejection
FR2720880B1 (en) 1994-06-06 1996-08-02 Fournier Jean Michel Device for removing the image signal of a base signal transposed to an intermediate frequency.
US5640415A (en) 1994-06-10 1997-06-17 Vlsi Technology, Inc. Bit error performance of a frequency hopping, radio communication system
US5517688A (en) 1994-06-20 1996-05-14 Motorola, Inc. MMIC FET mixer and method
US5907149A (en) 1994-06-27 1999-05-25 Polaroid Corporation Identification card with delimited usage
WO1996002977A1 (en) 1994-07-13 1996-02-01 Stanford Telecommunications, Inc. Method and apparatus for alias-driven frequency downconversion (mixing)
EP0696854A1 (en) 1994-08-08 1996-02-14 THOMSON multimedia S.A. Broadcast receiver adapted for analog and digital signals
JP3142222B2 (en) 1994-08-22 2001-03-07 松下電器産業株式会社 Spread spectrum communication synchronizing method and circuit device
US5703584A (en) 1994-08-22 1997-12-30 Adaptec, Inc. Analog data acquisition system
WO1996008078A1 (en) 1994-09-02 1996-03-14 Philips Electronics N.V. Receiver with quadrature decimation stage, method of processing digital signals
US5551076A (en) 1994-09-06 1996-08-27 Motorola, Inc. Circuit and method of series biasing a single-ended mixer
JP3577754B2 (en) 1994-09-09 2004-10-13 ソニー株式会社 COMMUNICATION METHOD AND APPARATUS
US5742189A (en) 1994-09-16 1998-04-21 Kabushiki Kaisha Toshiba Frequency conversion circuit and radio communication apparatus with the same
KR970000660B1 (en) 1994-09-27 1997-01-16 양승택 Satellite communication terminal site
WO1996011527A1 (en) 1994-10-07 1996-04-18 Massachusetts Institute Of Technology Quadrature sampling system and hybrid equalizer
GB2324919B (en) 1994-10-12 1999-01-27 Hewlett Packard Co Modulation and frequency conversion by time sharing
US5920842A (en) 1994-10-12 1999-07-06 Pixel Instruments Signal synchronization
US5523726A (en) 1994-10-13 1996-06-04 Westinghouse Electric Corporation Digital quadriphase-shift keying modulator
US5768323A (en) 1994-10-13 1998-06-16 Westinghouse Electric Corporation Symbol synchronizer using modified early/punctual/late gate technique
US5471665A (en) 1994-10-18 1995-11-28 Motorola, Inc. Differential DC offset compensation circuit
US5805460A (en) 1994-10-21 1998-09-08 Alliedsignal Inc. Method for measuring RF pulse rise time, fall time and pulse width
JP3581448B2 (en) 1994-10-21 2004-10-27 キヤノン株式会社 Spread spectrum communication device
US5953642A (en) 1994-10-26 1999-09-14 Siemens Aktiengesellschaft System for contactless power and data transmission
GB2294599B (en) 1994-10-28 1999-04-14 Marconi Instruments Ltd A frequency synthesiser
US5650785A (en) 1994-11-01 1997-07-22 Trimble Navigation Limited Low power GPS receiver
US5678226A (en) 1994-11-03 1997-10-14 Watkins Johnson Company Unbalanced FET mixer
DE69426650T2 (en) 1994-11-07 2001-09-06 Alcatel Sa Mixer for transmitters, with an input current mode
CN1087120C (en) 1994-11-10 2002-07-03 松下电器产业株式会社 Direct frequency conversion receiver
JP2950739B2 (en) 1994-11-11 1999-09-20 沖電気工業株式会社 Dual-mode transmission device
JP3478508B2 (en) 1994-11-22 2003-12-15 ユニデン株式会社 Wireless communication device
US5465410A (en) 1994-11-22 1995-11-07 Motorola, Inc. Method and apparatus for automatic frequency and bandwidth control
EP0714035A1 (en) * 1994-11-24 1996-05-29 The Furukawa Electric Co., Ltd. Radar device
US5680418A (en) 1994-11-28 1997-10-21 Ericsson, Inc. Removing low frequency interference in a digital FM receiver
US5515014A (en) 1994-11-30 1996-05-07 At&T Corp. Interface between SAW filter and Gilbert cell mixer
WO1996017441A1 (en) 1994-11-30 1996-06-06 Matsushita Electric Industrial Co., Ltd. Receiving circuit
US5648985A (en) 1994-11-30 1997-07-15 Rockwell Semiconductor Systems, Inc. Universal radio architecture for low-tier personal communication system
US5621455A (en) 1994-12-01 1997-04-15 Objective Communications, Inc. Video modem for transmitting video data over ordinary telephone wires
US5903178A (en) 1994-12-16 1999-05-11 Matsushita Electronics Corporation Semiconductor integrated circuit
US5714910A (en) 1994-12-19 1998-02-03 Efratom Time And Frequency Products, Inc. Methods and apparatus for digital frequency generation in atomic frequency standards
US5724653A (en) 1994-12-20 1998-03-03 Lucent Technologies Inc. Radio receiver with DC offset correction circuit
ZA9510509B (en) 1994-12-23 1996-05-30 Qualcomm Inc Dual-mode digital FM communication system
JP3084196B2 (en) 1994-12-27 2000-09-04 アイコム株式会社 Wireless communication device
US5579347A (en) 1994-12-28 1996-11-26 Telefonaktiebolaget Lm Ericsson Digitally compensated direct conversion receiver
US5748683A (en) 1994-12-29 1998-05-05 Motorola, Inc. Multi-channel transceiver having an adaptive antenna array and method
US5572262A (en) 1994-12-29 1996-11-05 Philips Electronics North America Corporation Receiver based methods and devices for combating co-channel NTSC interference in digital transmission
US5579341A (en) 1994-12-29 1996-11-26 Motorola, Inc. Multi-channel digital transceiver and method
US5668836A (en) 1994-12-29 1997-09-16 Motorola, Inc. Split frequency band signal digitizer and method
JP2571033B2 (en) 1994-12-30 1997-01-16 日本電気株式会社 The output control circuit of the transmission power amplifying circuit
JPH08223065A (en) 1995-02-13 1996-08-30 Toshiba Corp Frequency converter
US5995030A (en) 1995-02-16 1999-11-30 Advanced Micro Devices Apparatus and method for a combination D/A converter and FIR filter employing active current division from a single current source
DE69624020D1 (en) 1995-02-21 2002-11-07 Tait Electronics Ltd Zero intermediate frequency receiver
US5915278A (en) 1995-02-27 1999-06-22 Mallick; Brian C. System for the measurement of rotation and translation for modal analysis
FR2731310B1 (en) 1995-03-02 1997-04-11 Alcatel Telspace Device and method for receiving a single multirate filter interpolation and adaptation
US5606731A (en) * 1995-03-07 1997-02-25 Motorola, Inc. Zerox-IF receiver with tracking second local oscillator and demodulator phase locked loop oscillator
FR2731853B1 (en) 1995-03-17 1997-06-06 Valeo Electronique Method sampling and demodulation device, in particular for motor vehicle alarm system
US5697074A (en) 1995-03-30 1997-12-09 Nokia Mobile Phones Limited Dual rate power control loop for a transmitter
US5737035A (en) 1995-04-21 1998-04-07 Microtune, Inc. Highly integrated television tuner on a single microcircuit
JPH08307159A (en) 1995-04-27 1996-11-22 Sony Corp High frequency amplifier circuit, transmitter and receiver
US5640424A (en) 1995-05-16 1997-06-17 Interstate Electronics Corporation Direct downconverter circuit for demodulator in digital data transmission system
US5640698A (en) 1995-06-06 1997-06-17 Stanford University Radio frequency signal reception using frequency shifting by discrete-time sub-sampling down-conversion
US5793818A (en) 1995-06-07 1998-08-11 Discovision Associates Signal processing system
US5764087A (en) 1995-06-07 1998-06-09 Aai Corporation Direct digital to analog microwave frequency signal simulator
US5668831A (en) 1995-06-07 1997-09-16 Discovision Associates Signal processing apparatus and method
KR100395584B1 (en) 1995-06-08 2004-02-11 코닌클리케 필립스 일렉트로닉스 엔.브이. Transmission System Using a transmission having a phase modulator and a frequency multiplier,
US5812786A (en) 1995-06-21 1998-09-22 Bell Atlantic Network Services, Inc. Variable rate and variable mode transmission system
US5675392A (en) 1995-06-21 1997-10-07 Sony Corporation Mixer with common-mode noise rejection
US5903827A (en) 1995-07-07 1999-05-11 Fujitsu Compound Semiconductor, Inc. Single balanced frequency downconverter for direct broadcast satellite transmissions and hybrid ring signal combiner
JP3189631B2 (en) 1995-07-10 2001-07-16 株式会社村田製作所 The mixer
US5691629A (en) 1995-07-13 1997-11-25 The United States Of America As Represented By The Secretary Of The Air Force Non-volatile power supply having energy efficient DC/DC voltage converters with a small storage capacitor
US5745846A (en) 1995-08-07 1998-04-28 Lucent Technologies, Inc. Channelized apparatus for equalizing carrier powers of multicarrier signal
JP4091671B2 (en) 1995-08-08 2008-05-28 松下電器産業株式会社 DC offset compensation device
US5822373A (en) 1995-08-17 1998-10-13 Pittway Corporation Method and apparatus for optimization of wireless communications
US5757864A (en) 1995-08-17 1998-05-26 Rockwell Semiconductor Systems, Inc. Receiver with filters offset correction
AU7152896A (en) 1995-08-21 1997-03-12 Diasense, Inc. Synchronous detection for photoconductive detectors
US6026286A (en) 1995-08-24 2000-02-15 Nortel Networks Corporation RF amplifier, RF mixer and RF receiver
US5636140A (en) 1995-08-25 1997-06-03 Advanced Micro Devices, Inc. System and method for a flexible MAC layer interface in a wireless local area network
US5563550A (en) 1995-08-28 1996-10-08 Lockheed Martin Corporation Recovery of data from amplitude modulated signals with self-coherent demodulation
US6072994A (en) 1995-08-31 2000-06-06 Northrop Grumman Corporation Digitally programmable multifunction radio system architecture
US5903823A (en) 1995-09-19 1999-05-11 Fujitsu Limited Radio apparatus with distortion compensating function
DE69630512T2 (en) 1995-09-29 2004-05-06 Matsushita Electric Industrial Co., Ltd., Kadoma Power amplifier and communication device
FR2739938B1 (en) 1995-10-17 1997-11-07 Sextant Avionique determination of a position receiver from satellites networks
GB9521769D0 (en) 1995-10-24 1996-01-03 Philips Electronics Nv Transmitter
JPH09121124A (en) 1995-10-25 1997-05-06 Fujitsu Ltd Double balanced mixer circuit
US6034566A (en) 1995-11-07 2000-03-07 Takeshi Ikeda Tuning amplifier
FR2741221B1 (en) 1995-11-13 1997-12-05 Alcatel Telspace direct demodulation stage of a signal module in phase quadrature and receiver comprising such a demodulation stage
US5721514A (en) 1995-11-22 1998-02-24 Efratom Time And Frequency Products, Inc. Digital frequency generation in atomic frequency standards using digital phase shifting
US5778022A (en) 1995-12-06 1998-07-07 Rockwell International Corporation Extended time tracking and peak energy in-window demodulation for use in a direct sequence spread spectrum system
US5909460A (en) 1995-12-07 1999-06-01 Ericsson, Inc. Efficient apparatus for simultaneous modulation and digital beamforming for an antenna array
JP3406443B2 (en) 1995-12-08 2003-05-12 日本ビクター株式会社 Wireless transmission device
US5887001A (en) * 1995-12-13 1999-03-23 Bull Hn Information Systems Inc. Boundary scan architecture analog extension with direct connections
FR2742620B1 (en) 1995-12-15 1998-02-20 Matra Communication Mixing device has image frequency rejection
US5659372A (en) 1995-12-22 1997-08-19 Samsung Electronics Co., Ltd. Digital TV detector responding to final-IF signal with vestigial sideband below full sideband in frequency
JP3338747B2 (en) 1995-12-28 2002-10-28 日本電気株式会社 Interference elimination device
FR2743227B1 (en) 1995-12-29 1998-03-06 Thomson Broadcast Systems Demodulator device monolithically integrable frequency
FR2743231B1 (en) 1995-12-29 1998-01-30 Thomson Multimedia Sa Method and frequency diversity device of an SHF carrier
US7536331B1 (en) 1996-01-02 2009-05-19 Robert W. Fletcher Method for determining the risk associated with licensing or enforcing intellectual property
US5736895A (en) 1996-01-16 1998-04-07 Industrial Technology Research Institute Biquadratic switched-capacitor filter using single operational amplifier
US5901347A (en) 1996-01-17 1999-05-04 Motorola, Inc. Fast automatic gain control circuit and method for zero intermediate frequency receivers and radiotelephone using same
US5697091A (en) 1996-02-07 1997-12-09 Ford Motor Company Distortion-free chopper-based signal mixer
US6546061B2 (en) 1996-10-02 2003-04-08 Telefonaktiebolaget Lm Ericsson (Publ) Signal transformation method and apparatus
US5732333A (en) 1996-02-14 1998-03-24 Glenayre Electronics, Inc. Linear transmitter using predistortion
JP2782057B2 (en) 1996-02-19 1998-07-30 国際電気株式会社 Despreading circuit for spread spectrum communication system
US5729829A (en) 1996-02-29 1998-03-17 American Nucleonics Corporation Interference mitigation method and apparatus for multiple collocated transceivers
US5689413A (en) 1996-03-04 1997-11-18 Motorola, Inc. Voltage convertor for a portable electronic device
US6160280A (en) 1996-03-04 2000-12-12 Motorola, Inc. Field effect transistor
JP3712291B2 (en) 1996-03-12 2005-11-02 和夫 坪内 Wireless switch device using a surface acoustic wave device
GB2311194B (en) 1996-03-12 2000-05-31 Nokia Mobile Phones Ltd Transmitting and receiving radio signals
JPH09251651A (en) 1996-03-15 1997-09-22 Toshiba Corp Phase difference voltage generating circuit
DE19610760A1 (en) 1996-03-19 1997-09-25 Telefunken Microelectron Transmit-receive switch with semiconductors
CN1165438A (en) 1996-03-19 1997-11-19 三星电子株式会社 Frequency converter for outputting stable frequency
US5663878A (en) 1996-03-21 1997-09-02 Unitrode Corporation Apparatus and method for generating a low frequency AC signal
US5663986A (en) 1996-03-25 1997-09-02 The United States Of America As Represented By The Secretary Of The Navy Apparatus and method of transmitting data over a coaxial cable in a noisy environment
JP3125675B2 (en) 1996-03-29 2001-01-22 三菱電機株式会社 Capacitive sensor interface circuit
FI100286B (en) 1996-04-01 1997-10-31 Nokia Mobile Phones Ltd The transmitter / receiver of the RF signal transmitting and receiving two frequency bands
JPH10229378A (en) 1996-04-02 1998-08-25 Sharp Corp Matched filter
DE69735031D1 (en) 1996-04-04 2006-03-30 New Japan Radio Corp Ltd Correlator for spread spectrum
WO1997038490A1 (en) 1996-04-08 1997-10-16 Romano Harry A Interrupt modulation method and appratus
JP3255843B2 (en) 1996-04-17 2002-02-12 沖電気工業株式会社 Digital-to-analog shared circuit in the dual-mode radio device
US5754056A (en) 1996-04-23 1998-05-19 David Sarnoff Research Center, Inc. Charge detector with long integration time
EP0804038B1 (en) 1996-04-26 2004-07-07 Hamamatsu Photonics K.K. Solid-state image sensing device
US5768118A (en) 1996-05-01 1998-06-16 Compaq Computer Corporation Reciprocating converter
US5787125A (en) 1996-05-06 1998-07-28 Motorola, Inc. Apparatus for deriving in-phase and quadrature-phase baseband signals from a communication signal
US5729577A (en) 1996-05-21 1998-03-17 Motorola, Inc. Signal processor with improved efficiency
US6067329A (en) 1996-05-31 2000-05-23 Matsushita Electric Industrial Co., Ltd. VSB demodulator
US5724002A (en) 1996-06-13 1998-03-03 Acrodyne Industries, Inc. Envelope detector including sample-and-hold circuit controlled by preceding carrier pulse peak(s)
US5900746A (en) 1996-06-13 1999-05-04 Texas Instruments Incorporated Ultra low jitter differential to fullswing BiCMOS comparator with equal rise/fall time and complementary outputs
US5841324A (en) 1996-06-20 1998-11-24 Harris Corporation Charge-based frequency locked loop and method
US5930301A (en) 1996-06-25 1999-07-27 Harris Corporation Up-conversion mechanism employing side lobe-selective pre-distortion filter and frequency replica-selecting bandpass filter respectively installed upstream and downstream of digital-to-analog converter
US5884154A (en) * 1996-06-26 1999-03-16 Raytheon Company Low noise mixer circuit having passive inductor elements
DE69731358T2 (en) 1996-06-28 2005-11-03 Koninklijke Philips Electronics N.V. A method for simplifying the demodulation in a multi-carrier transmission system
US5898912A (en) 1996-07-01 1999-04-27 Motorola, Inc. Direct current (DC) offset compensation method and apparatus
US6005903A (en) 1996-07-08 1999-12-21 Mendelovicz; Ephraim Digital correlator
US5793801A (en) 1996-07-09 1998-08-11 Telefonaktiebolaget Lm Ericsson Frequency domain signal reconstruction compensating for phase adjustments to a sampling signal
US5699006A (en) 1996-07-12 1997-12-16 Motorola, Inc. DC blocking apparatus and technique for sampled data filters
US6028887A (en) 1996-07-12 2000-02-22 General Electric Company Power efficient receiver
US5896304A (en) 1996-07-12 1999-04-20 General Electric Company Low power parallel correlator for measuring correlation between digital signal segments
US5911123A (en) 1996-07-31 1999-06-08 Siemens Information And Communications Networks, Inc. System and method for providing wireless connections for single-premises digital telephones
US5802463A (en) 1996-08-20 1998-09-01 Advanced Micro Devices, Inc. Apparatus and method for receiving a modulated radio frequency signal by converting the radio frequency signal to a very low intermediate frequency signal
US6330244B1 (en) 1996-09-05 2001-12-11 Jerome Swartz System for digital radio communication between a wireless lan and a PBX
US5956345A (en) 1996-09-13 1999-09-21 Lucent Technologies Inc. IS-95 compatible wideband communication scheme
US5894496A (en) 1996-09-16 1999-04-13 Ericsson Inc. Method and apparatus for detecting and compensating for undesired phase shift in a radio transceiver
US5818582A (en) 1996-09-19 1998-10-06 Ciencia, Inc. Apparatus and method for phase fluorometry
US5870670A (en) * 1996-09-23 1999-02-09 Motorola, Inc. Integrated image reject mixer
SE519541C2 (en) 1996-10-02 2003-03-11 Ericsson Telefon Ab L M Method and apparatus for transforming a real digital wideband bandpass signal into a set of digital baseband signals with I and Q components
JPH10117220A (en) 1996-10-11 1998-05-06 Hitachi Denshi Ltd Digital demodulator
US5945660A (en) 1996-10-16 1999-08-31 Matsushita Electric Industrial Co., Ltd. Communication system for wireless bar code reader
US5767726A (en) 1996-10-21 1998-06-16 Lucent Technologies Inc. Four terminal RF mixer device
JPH10126307A (en) 1996-10-21 1998-05-15 Murata Mfg Co Ltd High-frequency composite component
US5909447A (en) 1996-10-29 1999-06-01 Stanford Telecommunications, Inc. Class of low cross correlation palindromic synchronization sequences for time tracking in synchronous multiple access communication systems
US6005887A (en) 1996-11-14 1999-12-21 Ericcsson, Inc. Despreading of direct sequence spread spectrum communications signals
US5905433A (en) 1996-11-25 1999-05-18 Highwaymaster Communications, Inc. Trailer communications system
DE19648915C2 (en) 1996-11-26 2001-02-22 Temic Semiconductor Gmbh Process for the frequency conversion
JP3557059B2 (en) 1996-11-27 2004-08-25 富士通株式会社 Pulse width control device
JPH10163756A (en) 1996-11-28 1998-06-19 Fujitsu Ltd Automatic frequency controller
FR2756686B1 (en) 1996-11-29 1999-02-19 Thomson Csf Method and mixed analog digital broadcast apparatus and the radio program by the same issuer
FR2756682B1 (en) 1996-12-03 1999-05-14 Schneider Electric Sa photocell stabilized amplification
JP3884115B2 (en) 1996-12-10 2007-02-21 三菱電機株式会社 Digital matched filter
US5886547A (en) 1996-12-16 1999-03-23 Motorola, Inc. Circuit and method of controlling mixer linearity
US5834985A (en) 1996-12-20 1998-11-10 Telefonaktiebolaget L M Ericsson (Publ) Digital continuous phase modulation for a DDS-driven phase locked loop
US5970053A (en) 1996-12-24 1999-10-19 Rdl, Inc. Method and apparatus for controlling peak factor of coherent frequency-division-multiplexed systems
JP3979690B2 (en) 1996-12-27 2007-09-19 富士通株式会社 The semiconductor storage system and a semiconductor memory device
US5937013A (en) 1997-01-03 1999-08-10 The Hong Kong University Of Science & Technology Subharmonic quadrature sampling receiver and design
US6031217A (en) 1997-01-06 2000-02-29 Texas Instruments Incorporated Apparatus and method for active integrator optical sensors
US5901348A (en) 1997-01-10 1999-05-04 Ail Systems, Inc. Apparatus for enhancing sensitivity in compressive receivers and method for the same
GB2321149B (en) 1997-01-11 2001-04-04 Plessey Semiconductors Ltd Low voltage double balanced mixer
GB2321352B (en) 1997-01-11 2001-04-04 Plessey Semiconductors Ltd Image reject mixer
US6009317A (en) 1997-01-17 1999-12-28 Ericsson Inc. Method and apparatus for compensating for imbalances between quadrature signals
US5926513A (en) 1997-01-27 1999-07-20 Alcatel Alsthom Compagnie Generale D'electricite Receiver with analog and digital channel selectivity
US5881375A (en) 1997-01-31 1999-03-09 Glenayre Electronics, Inc. Paging transmitter having broadband exciter using an intermediate frequency above the transmit frequency
US7356042B2 (en) 1999-06-03 2008-04-08 Tellabs Beford, Inc. Distributed ethernet hub
DE19703889C1 (en) 1997-02-03 1998-02-19 Bosch Gmbh Robert Scanning phase detector device
US6091939A (en) 1997-02-18 2000-07-18 Ericsson Inc. Mobile radio transmitter with normal and talk-around frequency bands
EP0862274A1 (en) 1997-02-26 1998-09-02 TELEFONAKTIEBOLAGET L M ERICSSON (publ) A method of and a device for analog signal sampling
DE19708163A1 (en) 1997-02-28 1998-09-10 Bosch Gmbh Robert Circuit for signal processing occurring in a heterodyne signals
JPH10247952A (en) 1997-03-05 1998-09-14 Fujitsu Ltd Phase modulator
JP3911788B2 (en) 1997-03-10 2007-05-09 ソニー株式会社 A solid-state imaging device and a driving method
US5918167A (en) 1997-03-11 1999-06-29 Northern Telecom Limited Quadrature downconverter local oscillator leakage canceller
EP0900481B1 (en) 1997-03-12 2006-06-14 Philips Electronics N.V. A frequency conversion circuit
US6072996A (en) 1997-03-28 2000-06-06 Intel Corporation Dual band radio receiver
US5903196A (en) 1997-04-07 1999-05-11 Motorola, Inc. Self centering frequency multiplier
US5878088A (en) * 1997-04-10 1999-03-02 Thomson Consumer Electronics, Inc. Digital variable symbol timing recovery system for QAM
JPH10294676A (en) 1997-04-17 1998-11-04 Yozan:Kk Standby circuit
US5894239A (en) 1997-04-18 1999-04-13 International Business Machines Corporation Single shot with pulse width controlled by reference oscillator
US6038265A (en) * 1997-04-21 2000-03-14 Motorola, Inc. Apparatus for amplifying a signal using digital pulse width modulators
GB2325102B (en) 1997-05-09 2001-10-10 Nokia Mobile Phones Ltd Down conversion mixer
JP3413060B2 (en) 1997-05-13 2003-06-03 松下電器産業株式会社 Direct conversion receiver
US7209523B1 (en) 1997-05-16 2007-04-24 Multispectral Solutions, Inc. Ultra-wideband receiver and transmitter
US6026125A (en) * 1997-05-16 2000-02-15 Multispectral Solutions, Inc. Waveform adaptive ultra-wideband transmitter
US5999561A (en) 1997-05-20 1999-12-07 Sanconix, Inc. Direct sequence spread spectrum method, computer-based product, apparatus and system tolerant to frequency reference offset
GB2326038A (en) 1997-06-06 1998-12-09 Nokia Mobile Phones Ltd Signal level balancing in quadrature receiver
US5825257A (en) 1997-06-17 1998-10-20 Telecommunications Research Laboratories GMSK modulator formed of PLL to which continuous phase modulated signal is applied
US6608647B1 (en) 1997-06-24 2003-08-19 Cognex Corporation Methods and apparatus for charge coupled device image acquisition with independent integration and readout
CN1139273C (en) 1997-06-27 2004-02-18 皇家菲利浦电子有限公司 Radio communication device with low power consumption and good spectral range
US5907197A (en) 1997-06-30 1999-05-25 Compaq Computer Corporation AC/DC portable power connecting architecture
KR100268648B1 (en) 1997-07-14 2000-10-16 이계철 Low frequency filter
US6223061B1 (en) 1997-07-25 2001-04-24 Cleveland Medical Devices Inc. Apparatus for low power radio communications
US5834987A (en) 1997-07-30 1998-11-10 Ercisson Inc. Frequency synthesizer systems and methods for three-point modulation with a DC response
EP0895386B1 (en) 1997-07-31 2003-01-29 Micronas Semiconductor Holding AG Carrier control circuit for a receiver of digital transmitted signals
US6240100B1 (en) 1997-07-31 2001-05-29 Motorola, Inc. Cellular TDMA base station receiver with dynamic DC offset correction
US5892380A (en) 1997-08-04 1999-04-06 Motorola, Inc. Method for shaping a pulse width and circuit therefor
WO1999008389A2 (en) 1997-08-12 1999-02-18 Koninklijke Philips Electronics N.V. A digital communication device and a mixer
US5872446A (en) * 1997-08-12 1999-02-16 International Business Machines Corporation Low voltage CMOS analog multiplier with extended input dynamic range
DE19735798C1 (en) 1997-08-18 1998-07-16 Siemens Ag Transceiver device for mobile radio telephone
US6128746A (en) 1997-08-26 2000-10-03 International Business Machines Corporation Continuously powered mainstore for large memory subsystems
US6298065B1 (en) 1997-08-29 2001-10-02 Lucent Technologies Inc. Method for multi-mode operation of a subscriber line card in a telecommunications system
US5982315A (en) 1997-09-12 1999-11-09 Qualcomm Incorporated Multi-loop Σ Δ analog to digital converter
IT1294732B1 (en) * 1997-09-15 1999-04-12 Italtel Spa Converter subharmonic frequencies image rejection realized in microstrip, particularly suitable for use in
US5949827A (en) 1997-09-19 1999-09-07 Motorola, Inc. Continuous integration digital demodulator for use in a communication device
US6047026A (en) 1997-09-30 2000-04-04 Ohm Technologies International, Llc Method and apparatus for automatic equalization of very high frequency multilevel and baseband codes using a high speed analog decision feedback equalizer
JPH11112882A (en) 1997-09-30 1999-04-23 Olympus Optical Co Ltd Image pickup device
SE514795C2 (en) 1997-10-03 2001-04-23 Ericsson Telefon Ab L M Device and method for up- and down-conversion
US6385439B1 (en) 1997-10-31 2002-05-07 Telefonaktiebolaget Lm Ericsson (Publ) Linear RF power amplifier with optically activated switches
US5883548A (en) 1997-11-10 1999-03-16 The United States Of America As Represented By The Secretary Of The Navy Demodulation system and method for recovering a signal of interest from an undersampled, modulated carrier
US6054889A (en) 1997-11-11 2000-04-25 Trw Inc. Mixer with improved linear range
US6330292B1 (en) 1997-11-11 2001-12-11 Telefonaktiebolaget Lm Ericsson Reduced power matched filter
US6567483B1 (en) 1997-11-11 2003-05-20 Ericsson, Inc. Matched filter using time-multiplexed precombinations
KR100297340B1 (en) 1997-11-18 2001-05-21 이형도 Asymmetry flyback converter
US6005506A (en) 1997-12-09 1999-12-21 Qualcomm, Incorporated Receiver with sigma-delta analog-to-digital converter for sampling a received signal
US6049573A (en) 1997-12-11 2000-04-11 Massachusetts Institute Of Technology Efficient polyphase quadrature digital tuner
JP3070733B2 (en) 1997-12-12 2000-07-31 日本電気株式会社 Automatic frequency control method and apparatus
JPH11177646A (en) 1997-12-12 1999-07-02 Matsushita Electric Ind Co Ltd Demodulator
US5901054A (en) 1997-12-18 1999-05-04 Chun-Shan Institute Of Science And Technology Pulse-width-modulation control circuit
US6151354A (en) 1997-12-19 2000-11-21 Rockwell Science Center Multi-mode, multi-band, multi-user radio system architecture
GB2332822B (en) 1997-12-23 2002-08-28 Nortel Networks Corp Communication device having a wideband receiver and operating method therefor
US6144846A (en) 1997-12-31 2000-11-07 Motorola, Inc. Frequency translation circuit and method of translating
US6098886A (en) 1998-01-21 2000-08-08 Symbol Technologies, Inc. Glove-mounted system for reading bar code symbols
US5986600A (en) 1998-01-22 1999-11-16 Mcewan; Thomas E. Pulsed RF oscillator and radar motion sensor
US6144236A (en) 1998-02-01 2000-11-07 Bae Systems Aerospace Electronics Inc. Structure and method for super FET mixer having logic-gate generated FET square-wave switching signal
US6686879B2 (en) 1998-02-12 2004-02-03 Genghiscomm, Llc Method and apparatus for transmitting and receiving signals having a carrier interferometry architecture
US5955992A (en) 1998-02-12 1999-09-21 Shattil; Steve J. Frequency-shifted feedback cavity used as a phased array antenna controller and carrier interference multiple access spread-spectrum transmitter
US5952895A (en) 1998-02-23 1999-09-14 Tropian, Inc. Direct digital synthesis of precise, stable angle modulated RF signal
US6076015A (en) 1998-02-27 2000-06-13 Cardiac Pacemakers, Inc. Rate adaptive cardiac rhythm management device using transthoracic impedance
US6195539B1 (en) * 1998-03-02 2001-02-27 Mentor Graphics Corporation Method and apparatus for rejecting image signals in a receiver
US6085073A (en) 1998-03-02 2000-07-04 Motorola, Inc. Method and system for reducing the sampling rate of a signal for use in demodulating high modulation index frequency modulated signals
US6125271A (en) 1998-03-06 2000-09-26 Conexant Systems, Inc. Front end filter circuitry for a dual band GSM/DCS cellular phone
US6150890A (en) 1998-03-19 2000-11-21 Conexant Systems, Inc. Dual band transmitter for a cellular phone comprising a PLL
JPH11346172A (en) 1998-03-30 1999-12-14 Kokusai Electric Co Ltd Receiver
US6121819A (en) 1998-04-06 2000-09-19 Motorola, Inc. Switching down conversion mixer for use in multi-stage receiver architectures
US6144331A (en) 1998-04-08 2000-11-07 Texas Instruments Incorporated Analog to digital converter with a differential output resistor-digital-to-analog-converter for improved noise reduction
US6208875B1 (en) 1998-04-08 2001-03-27 Conexant Systems, Inc. RF architecture for cellular dual-band telephones
US6044332A (en) 1998-04-15 2000-03-28 Lockheed Martin Energy Research Corporation Surface acoustic wave harmonic analysis
US6192225B1 (en) 1998-04-22 2001-02-20 Ericsson Inc. Direct conversion receiver
US6078630A (en) 1998-04-23 2000-06-20 Lucent Technologies Inc. Phase-based receiver with multiple sampling frequencies
US6084465A (en) 1998-05-04 2000-07-04 Tritech Microelectronics, Ltd. Method for time constant tuning of gm-C filters
DE19823049C2 (en) 1998-05-22 2000-09-21 Ericsson Telefon Ab L M Power amplifier output circuit for the suppression of harmonics for a mobile unit with dual-band operation and method of operating the same
US6324379B1 (en) 1998-05-28 2001-11-27 California Amplifier, Inc. Transceiver systems and methods that preserve frequency order when downconverting communication signals and upconverting data signals
US6208636B1 (en) 1998-05-28 2001-03-27 Northpoint Technology, Ltd. Apparatus and method for processing signals selected from multiple data streams
US6057714A (en) 1998-05-29 2000-05-02 Conexant Systems, Inc. Double balance differential active ring mixer with current shared active input balun
FI120124B (en) 1998-05-29 2009-06-30 Nokia Corp A method and circuit for sampling the signal at a high sampling
US5973568A (en) 1998-06-01 1999-10-26 Motorola Inc. Power amplifier output module for dual-mode digital systems
US6212369B1 (en) 1998-06-05 2001-04-03 Maxim Integrated Products, Inc. Merged variable gain mixers
US6314279B1 (en) 1998-06-29 2001-11-06 Philips Electronics North America Corporation Frequency offset image rejection
US6404823B1 (en) 1998-07-01 2002-06-11 Conexant Systems, Inc. Envelope feedforward technique with power control for efficient linear RF power amplification
US6865399B2 (en) 2000-10-26 2005-03-08 Renesas Technology Corp. Mobile telephone apparatus
US6088348A (en) 1998-07-13 2000-07-11 Qualcom Incorporated Configurable single and dual VCOs for dual- and tri-band wireless communication systems
US6167247A (en) 1998-07-15 2000-12-26 Lucent Technologies, Inc. Local oscillator leak cancellation circuit
EP0977351B1 (en) 1998-07-30 2004-02-18 Motorola Semiconducteurs S.A. Method and apparatus for radio communication
US6188221B1 (en) 1998-08-07 2001-02-13 Van De Kop Franz Method and apparatus for transmitting electromagnetic waves and analyzing returns to locate underground fluid deposits
US6198941B1 (en) * 1998-08-07 2001-03-06 Lucent Technologies Inc. Method of operating a portable communication device
US6694128B1 (en) * 1998-08-18 2004-02-17 Parkervision, Inc. Frequency synthesizer using universal frequency translation technology
US6094084A (en) 1998-09-04 2000-07-25 Nortel Networks Corporation Narrowband LC folded cascode structure
US5982329A (en) 1998-09-08 1999-11-09 The United States Of America As Represented By The Secretary Of The Army Single channel transceiver with polarization diversity
US6041073A (en) 1998-09-18 2000-03-21 Golden Bridge Technology, Inc. Multi-clock matched filter for receiving signals with multipath
US6147340A (en) 1998-09-29 2000-11-14 Raytheon Company Focal plane readout unit cell background suppression circuit and method
EP1033820A4 (en) 1998-09-30 2004-08-11 Mitsubishi Electric Corp Even harmonic direct conversion receiver and a transceiver comprising the same
US6963626B1 (en) 1998-10-02 2005-11-08 The Board Of Trustees Of The Leland Stanford Junior University Noise-reducing arrangement and method for signal processing
US6230000B1 (en) 1998-10-15 2001-05-08 Motorola Inc. Product detector and method therefor
US7295826B1 (en) 1998-10-21 2007-11-13 Parkervision, Inc. Integrated frequency translation and selectivity with gain control functionality, and applications thereof
US6049706A (en) 1998-10-21 2000-04-11 Parkervision, Inc. Integrated frequency translation and selectivity
US6813485B2 (en) 1998-10-21 2004-11-02 Parkervision, Inc. Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same
US6061555A (en) 1998-10-21 2000-05-09 Parkervision, Inc. Method and system for ensuring reception of a communications signal
US7039372B1 (en) 1998-10-21 2006-05-02 Parkervision, Inc. Method and system for frequency up-conversion with modulation embodiments
US6061551A (en) 1998-10-21 2000-05-09 Parkervision, Inc. Method and system for down-converting electromagnetic signals
US6370371B1 (en) 1998-10-21 2002-04-09 Parkervision, Inc. Applications of universal frequency translation
US6873836B1 (en) * 1999-03-03 2005-03-29 Parkervision, Inc. Universal platform module and methods and apparatuses relating thereto enabled by universal frequency translation technology
US6091940A (en) * 1998-10-21 2000-07-18 Parkervision, Inc. Method and system for frequency up-conversion
US7236754B2 (en) 1999-08-23 2007-06-26 Parkervision, Inc. Method and system for frequency up-conversion
US6560301B1 (en) 1998-10-21 2003-05-06 Parkervision, Inc. Integrated frequency translation and selectivity with a variety of filter embodiments
US6542722B1 (en) 1998-10-21 2003-04-01 Parkervision, Inc. Method and system for frequency up-conversion with variety of transmitter configurations
US7010286B2 (en) 2000-04-14 2006-03-07 Parkervision, Inc. Apparatus, system, and method for down-converting and up-converting electromagnetic signals
US8406724B2 (en) 1998-10-21 2013-03-26 Parkervision, Inc. Applications of universal frequency translation
US7515896B1 (en) 1998-10-21 2009-04-07 Parkervision, Inc. Method and system for down-converting an electromagnetic signal, and transforms for same, and aperture relationships
US6366622B1 (en) 1998-12-18 2002-04-02 Silicon Wave, Inc. Apparatus and method for wireless communications
GB9828230D0 (en) 1998-12-21 1999-02-17 Nokia Telecommunications Oy Receiver and method of receiving
US6137321A (en) 1999-01-12 2000-10-24 Qualcomm Incorporated Linear sampling switch
US7006805B1 (en) * 1999-01-22 2006-02-28 Parker Vision, Inc. Aliasing communication system with multi-mode and multi-band functionality and embodiments thereof, such as the family radio service
US7209725B1 (en) 1999-01-22 2007-04-24 Parkervision, Inc Analog zero if FM decoder and embodiments thereof, such as the family radio service
US6704558B1 (en) 1999-01-22 2004-03-09 Parkervision, Inc. Image-reject down-converter and embodiments thereof, such as the family radio service
US6704549B1 (en) * 1999-03-03 2004-03-09 Parkvision, Inc. Multi-mode, multi-band communication system
US7110435B1 (en) 1999-03-15 2006-09-19 Parkervision, Inc. Spread spectrum applications of universal frequency translation
US7072636B2 (en) 1999-03-25 2006-07-04 Zenith Electronics Corporation Printed circuit doubly balanced mixer for upconverter
US6114980A (en) 1999-04-13 2000-09-05 Motorola, Inc. Method and apparatus for settling a DC offset
US7065162B1 (en) 1999-04-16 2006-06-20 Parkervision, Inc. Method and system for down-converting an electromagnetic signal, and transforms for same
US8295406B1 (en) 1999-08-04 2012-10-23 Parkervision, Inc. Universal platform module for a plurality of communication protocols
US6963734B2 (en) 1999-12-22 2005-11-08 Parkervision, Inc. Differential frequency down-conversion using techniques of universal frequency translation technology
US7693230B2 (en) 1999-04-16 2010-04-06 Parkervision, Inc. Apparatus and method of differential IQ frequency up-conversion
US7110444B1 (en) 1999-08-04 2006-09-19 Parkervision, Inc. Wireless local area network (WLAN) using universal frequency translation technology including multi-phase embodiments and circuit implementations
US6853690B1 (en) * 1999-04-16 2005-02-08 Parkervision, Inc. Method, system and apparatus for balanced frequency up-conversion of a baseband signal and 4-phase receiver and transceiver embodiments
US6404758B1 (en) 1999-04-19 2002-06-11 Ericsson, Inc. System and method for achieving slot synchronization in a wideband CDMA system in the presence of large initial frequency errors
CA2270516C (en) 1999-04-30 2009-11-17 Mosaid Technologies Incorporated Frequency-doubling delay locked loop
US6445726B1 (en) 1999-04-30 2002-09-03 Texas Instruments Incorporated Direct conversion radio receiver using combined down-converting and energy spreading mixing signal
WO2000072441A1 (en) 1999-05-24 2000-11-30 Level One Communications, Inc. Automatic gain control and offset correction
US6313685B1 (en) 1999-05-24 2001-11-06 Level One Communications, Inc. Offset cancelled integrator
US6307894B2 (en) * 1999-05-25 2001-10-23 Conexant Systems, Inc. Power amplification using a direct-upconverting quadrature mixer topology
JP4245227B2 (en) 1999-06-03 2009-03-25 シャープ株式会社 Digital matched filter
JP2000357951A (en) 1999-06-15 2000-12-26 Mitsubishi Electric Corp Delay circuit, clock generation circuit and phase locked loop
US7072390B1 (en) 1999-08-04 2006-07-04 Parkervision, Inc. Wireless local area network (WLAN) using universal frequency translation technology including multi-phase embodiments
US7054296B1 (en) 1999-08-04 2006-05-30 Parkervision, Inc. Wireless local area network (WLAN) technology and applications including techniques of universal frequency translation
JP3677181B2 (en) 1999-09-06 2005-07-27 株式会社東芝 Variable resistor circuit and d / a converter
US6647270B1 (en) 1999-09-10 2003-11-11 Richard B. Himmelstein Vehicletalk
US6618579B1 (en) 1999-09-24 2003-09-09 Chase Manhattan Bank Tunable filter with bypass
US6894988B1 (en) 1999-09-29 2005-05-17 Intel Corporation Wireless apparatus having multiple coordinated transceivers for multiple wireless communication protocols
FI114887B (en) 1999-10-13 2005-01-14 U Nav Microelectronics Corp Spread spectrum signal search system
US6560451B1 (en) 1999-10-15 2003-05-06 Cirrus Logic, Inc. Square wave analog multiplier
US7130579B1 (en) 1999-10-21 2006-10-31 Broadcom Corporation Adaptive radio transceiver with a wide tuning range VCO
US7554508B2 (en) 2000-06-09 2009-06-30 Parker Vision, Inc. Phased array antenna applications on universal frequency translation
US7082171B1 (en) 1999-11-24 2006-07-25 Parkervision, Inc. Phase shifting applications of universal frequency translation
US6697603B1 (en) 1999-12-13 2004-02-24 Andrew Corporation Digital repeater
JP3533351B2 (en) 1999-12-28 2004-05-31 日本無線株式会社 Feedforward amplifier and a control circuit
US6327313B1 (en) 1999-12-29 2001-12-04 Motorola, Inc. Method and apparatus for DC offset correction
US6634555B1 (en) 2000-01-24 2003-10-21 Parker Vision, Inc. Bar code scanner using universal frequency translation technology for up-conversion and down-conversion
US7292835B2 (en) 2000-01-28 2007-11-06 Parkervision, Inc. Wireless and wired cable modem applications of universal frequency translation technology
US6321073B1 (en) 2000-01-31 2001-11-20 Motorola, Inc. Radiotelephone receiver and method with improved dynamic range and DC offset correction
US6459889B1 (en) 2000-02-29 2002-10-01 Motorola, Inc. DC offset correction loop for radio receiver
US6625470B1 (en) 2000-03-02 2003-09-23 Motorola, Inc. Transmitter
US6741650B1 (en) 2000-03-02 2004-05-25 Adc Telecommunications, Inc. Architecture for intermediate frequency encoder
US6973476B1 (en) 2000-03-10 2005-12-06 Atheros Communications System and method for communicating data via a wireless high speed link
JP2001283107A (en) 2000-03-29 2001-10-12 Sony Corp System and device and method for managing sales task
US7193965B1 (en) * 2000-05-04 2007-03-20 Intel Corporation Multi-wireless network configurable behavior
US6731146B1 (en) 2000-05-09 2004-05-04 Qualcomm Incorporated Method and apparatus for reducing PLL lock time
US6591310B1 (en) 2000-05-11 2003-07-08 Lsi Logic Corporation Method of responding to I/O request and associated reply descriptor
KR100374929B1 (en) 2000-06-02 2003-03-06 학교법인 한국정보통신학원 Mixer
US6813320B1 (en) 2000-06-28 2004-11-02 Northrop Grumman Corporation Wireless telecommunications multi-carrier receiver architecture
US6992990B2 (en) * 2000-07-17 2006-01-31 Sony Corporation Radio communication apparatus
US6437639B1 (en) 2000-07-18 2002-08-20 Lucent Technologies Inc. Programmable RC filter
JP3570359B2 (en) 2000-08-24 2004-09-29 三菱電機株式会社 The high-frequency module
SE519333C2 (en) 2000-08-25 2003-02-18 Ericsson Telefon Ab L M Mixer comprising noise reducing passive filter
US6829311B1 (en) 2000-09-19 2004-12-07 Kaben Research Inc. Complex valued delta sigma phase locked loop demodulator
JP3489621B2 (en) 2000-09-28 2004-01-26 日本電気株式会社 Baseband circuit of the direct conversion receiver
AU2445002A (en) 2000-11-03 2002-05-15 Aryya Communications Inc Wideband multi-protocol wireless radio transceiver system
US7010559B2 (en) 2000-11-14 2006-03-07 Parkervision, Inc. Method and apparatus for a parallel correlator and applications thereof
US7454453B2 (en) 2000-11-14 2008-11-18 Parkervision, Inc. Methods, systems, and computer program products for parallel correlation and applications thereof
WO2002045283A2 (en) * 2000-11-29 2002-06-06 Broadcom Corporation Integrated direct conversion satellite tuner
US6441694B1 (en) 2000-12-15 2002-08-27 Motorola, Inc. Method and apparatus for generating digitally modulated signals
US6823178B2 (en) 2001-02-14 2004-11-23 Ydi Wireless, Inc. High-speed point-to-point modem-less microwave radio frequency link using direct frequency modulation
US20020132642A1 (en) 2001-03-16 2002-09-19 Hines John Ned Common module combiner/active array multicarrier approach without linearization loops
US7522900B2 (en) 2001-03-20 2009-04-21 Broadcom Corporation DC offset correction for use in a radio architecture
US6597240B1 (en) 2001-04-02 2003-07-22 Cirrus Logic, Inc. Circuits and methods for slew rate control and current limiting in switch-mode systems
US6741139B2 (en) 2001-05-22 2004-05-25 Ydi Wirelesss, Inc. Optical to microwave converter using direct modulation phase shift keying
US6850742B2 (en) 2001-06-01 2005-02-01 Sige Semiconductor Inc. Direct conversion receiver
US7072433B2 (en) 2001-07-11 2006-07-04 Micron Technology, Inc. Delay locked loop fine tune
US20030149579A1 (en) 2001-08-10 2003-08-07 Begemann Edwin Philip Method of increasing functionality of a product
US6690232B2 (en) 2001-09-27 2004-02-10 Kabushiki Kaisha Toshiba Variable gain amplifier
US6917796B2 (en) 2001-10-04 2005-07-12 Scientific Components Triple balanced mixer
US20030078011A1 (en) 2001-10-18 2003-04-24 Integrated Programmable Communications, Inc. Method for integrating a plurality of radio systems in a unified transceiver structure and the device of the same
JP3607238B2 (en) * 2001-10-22 2005-01-05 株式会社東芝 Ofdm signal reception system
US7072427B2 (en) 2001-11-09 2006-07-04 Parkervision, Inc. Method and apparatus for reducing DC offsets in a communication system
US7085335B2 (en) 2001-11-09 2006-08-01 Parkervision, Inc. Method and apparatus for reducing DC offsets in a communication system
FR2836305B1 (en) 2002-02-15 2004-05-07 St Microelectronics Sa Mixer differential class AB
US6903535B2 (en) 2002-04-16 2005-06-07 Arques Technology, Inc. Biasing system and method for low voltage DC—DC converters with built-in N-FETs
US6959178B2 (en) 2002-04-22 2005-10-25 Ipr Licensing Inc. Tunable upconverter mixer with image rejection
US7194044B2 (en) 2002-05-22 2007-03-20 Alexander Neil Birkett Up/down conversion circuitry for radio transceiver
US6975848B2 (en) 2002-06-04 2005-12-13 Parkervision, Inc. Method and apparatus for DC offset removal in a radio frequency communication channel
US7460584B2 (en) 2002-07-18 2008-12-02 Parkervision, Inc. Networking methods and systems
US7379883B2 (en) 2002-07-18 2008-05-27 Parkervision, Inc. Networking methods and systems
US6892057B2 (en) 2002-08-08 2005-05-10 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for reducing dynamic range of a power amplifier
JP2004201044A (en) 2002-12-19 2004-07-15 Sony Ericsson Mobilecommunications Japan Inc Portable communication terminal device and gain variable circuit
US20040125879A1 (en) 2002-12-31 2004-07-01 Jaussi James E. Information transmission unit
US6999747B2 (en) 2003-06-22 2006-02-14 Realtek Semiconductor Corp. Passive harmonic switch mixer
US7206566B1 (en) 2004-07-21 2007-04-17 Hrl Laboratories, Llc Apparatus and method for frequency conversion
US7358801B2 (en) 2004-08-16 2008-04-15 Texas Instruments Incorporated Reducing noise and/or power consumption in a switched capacitor amplifier sampling a reference voltage

Patent Citations (99)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270385A (en) * 1938-10-10 1942-01-20 Hartford Nat Bank & Trust Co Multicarrier transmission system
US2462069A (en) * 1942-05-07 1949-02-22 Int Standard Electric Corp Radio communication system
US2462181A (en) * 1944-09-28 1949-02-22 Western Electric Co Radio transmitting system
US2499279A (en) * 1947-04-22 1950-02-28 Ericsson Telefon Ab L M Single side band modulator
US2497859A (en) * 1947-11-19 1950-02-21 Western Union Telegraph Co Frequency diversity telegraph system
US3118117A (en) * 1959-10-30 1964-01-14 Int Standard Electric Corp Modulators for carrier communication systems
US3023309A (en) * 1960-12-19 1962-02-27 Bell Telephone Labor Inc Communication system
US3555428A (en) * 1966-10-03 1971-01-12 Xerox Corp Fsk receiver for detecting a data signal with the same number of cycles of each carrier frequency
US3717844A (en) * 1969-04-03 1973-02-20 Inst Francais Du Petrole Process of high reliability for communications between a master installation and secondary installations and device for carrying out this process
US3643168A (en) * 1969-07-07 1972-02-15 Standard Kallsman Ind Inc Solid-state tuned uhf television tuner
US3716730A (en) * 1971-04-19 1973-02-13 Motorola Inc Intermodulation rejection capabilities of field-effect transistor radio frequency amplifiers and mixers
US3714577A (en) * 1971-05-06 1973-01-30 W Hayes Single sideband am-fm modulation system
US3868601A (en) * 1973-06-18 1975-02-25 Us Navy Digital single-sideband modulator
US4066841A (en) * 1974-01-25 1978-01-03 Serck Industries Limited Data transmitting systems
US4003002A (en) * 1974-09-12 1977-01-11 U.S. Philips Corporation Modulation and filtering device
US3940697A (en) * 1974-12-02 1976-02-24 Hy-Gain Electronics Corporation Multiple band scanning radio
US4132952A (en) * 1975-11-11 1979-01-02 Sony Corporation Multi-band tuner with fixed broadband input filters
US4066919A (en) * 1976-04-01 1978-01-03 Motorola, Inc. Sample and hold circuit
US4142155A (en) * 1976-05-19 1979-02-27 Nippon Telegraph And Telephone Public Corporation Diversity system
US4253069A (en) * 1978-03-31 1981-02-24 Siemens Aktiengesellschaft Filter circuit having a biquadratic transfer function
US4369522A (en) * 1978-07-03 1983-01-18 Motorola, Inc. Singly-balanced active mixer circuit
US4253067A (en) * 1978-12-11 1981-02-24 Rockwell International Corporation Baseband differentially phase encoded radio signal detector
US4313222A (en) * 1979-05-25 1982-01-26 Blaupunkt Werke Gmbh H-F Portion of TV receiver
US4250458A (en) * 1979-05-31 1981-02-10 Digital Communications Corporation Baseband DC offset detector and control circuit for DC coupled digital demodulator
US4245355A (en) * 1979-08-08 1981-01-13 Eaton Corporation Microwave frequency converter
US4370572A (en) * 1980-01-17 1983-01-25 Trw Inc. Differential sample-and-hold circuit
US4430629A (en) * 1980-04-25 1984-02-07 Siemens Aktiengesellschaft Electrical filter circuit operated with a definite sampling and clock frequency fT which consists of CTD elements
US4253066A (en) * 1980-05-13 1981-02-24 Fisher Charles B Synchronous detection with sampling
US4563773A (en) * 1984-03-12 1986-01-07 The United States Of America As Represented By The Secretary Of The Army Monolithic planar doped barrier subharmonic mixer
US4893316A (en) * 1985-04-04 1990-01-09 Motorola, Inc. Digital radio frequency receiver
US4718113A (en) * 1985-05-08 1988-01-05 Alcatel Nv Zero-IF receiver wih feedback loop for suppressing interfering signals
US4726041A (en) * 1985-07-03 1988-02-16 Siemens Aktiengesellschaft Digital filter switch for data receiver
US4634998A (en) * 1985-07-17 1987-01-06 Hughes Aircraft Company Fast phase-lock frequency synthesizer with variable sampling efficiency
US4801823A (en) * 1986-09-10 1989-01-31 Nippon Gakki Seizo Kabushiki Kaisha Sample hold circuit
US4806790A (en) * 1987-02-16 1989-02-21 Nec Corporation Sample-and-hold circuit
US4995055A (en) * 1988-06-16 1991-02-19 Hughes Aircraft Company Time shared very small aperture satellite terminals
US4894766A (en) * 1988-11-25 1990-01-16 Hazeltine Corporation Power supply frequency converter
US4984077A (en) * 1988-12-28 1991-01-08 Victor Company Of Japan, Ltd. Signal converting apparatus
US4896152A (en) * 1989-03-02 1990-01-23 General Electric Company Telemetry system with a sending station using recursive filter for bandwidth limiting
US4902979A (en) * 1989-03-10 1990-02-20 General Electric Company Homodyne down-converter with digital Hilbert transform filtering
US5091921A (en) * 1989-04-20 1992-02-25 Nec Corporation Direct conversion receiver with dithering local carrier frequency for detecting transmitted carrier frequency
US5179731A (en) * 1989-06-09 1993-01-12 Licentia-Patent-Verwaltungs-Gmbh Frequency conversion circuit
US4893341A (en) * 1989-08-01 1990-01-09 At&E Corporation Digital receiver operating at sub-nyquist sampling rate
US4982353A (en) * 1989-09-28 1991-01-01 General Electric Company Subsampling time-domain digital filter using sparsely clocked output latch
US5379141A (en) * 1989-12-04 1995-01-03 Scientific-Atlanta, Inc. Method and apparatus for transmitting broadband amplitude modulated radio frequency signals over optical links
US5083050A (en) * 1990-11-30 1992-01-21 Grumman Aerospace Corporation Modified cascode mixer circuit
US5287516A (en) * 1991-01-10 1994-02-15 Landis & Gyr Betriebs Ag Demodulation process for binary data
US5278826A (en) * 1991-04-11 1994-01-11 Usa Digital Radio Method and apparatus for digital audio broadcasting and reception
US5490176A (en) * 1991-10-21 1996-02-06 Societe Anonyme Dite: Alcatel Telspace Detecting false-locking and coherent digital demodulation using the same
US5379040A (en) * 1992-02-17 1995-01-03 Nec Corporation Digital-to-analog converter
US5282222A (en) * 1992-03-31 1994-01-25 Michel Fattouche Method and apparatus for multiple access between transceivers in wireless communications using OFDM spread spectrum
US5282023A (en) * 1992-05-14 1994-01-25 Hitachi America, Ltd. Apparatus for NTSC signal interference cancellation through the use of digital recursive notch filters
US5483691A (en) * 1992-06-08 1996-01-09 Motorola, Inc. Zero intermediate frequency receiver having an automatic gain control circuit
US5493581A (en) * 1992-08-14 1996-02-20 Harris Corporation Digital down converter and method
US5483245A (en) * 1992-08-26 1996-01-09 Kollmorgen Artus ILS signal analysis device and method
US5390215A (en) * 1992-10-13 1995-02-14 Hughes Aircraft Company Multi-processor demodulator for digital cellular base station employing partitioned demodulation procedure with pipelined execution
US5390364A (en) * 1992-11-02 1995-02-14 Harris Corporation Least-mean squares adaptive digital filter havings variable size loop bandwidth
US5493721A (en) * 1992-11-07 1996-02-20 Grundig E.M.V. Receiver for a digital radio signal
US5388063A (en) * 1992-11-18 1995-02-07 Yozan Inc. Filter circuit with switchable finite impulse response and infinite impulse response filter characteristics
US5602868A (en) * 1993-02-17 1997-02-11 Motorola, Inc. Multiple-modulation communication system
US5389839A (en) * 1993-03-03 1995-02-14 Motorola, Inc. Integratable DC blocking circuit
US5495200A (en) * 1993-04-06 1996-02-27 Analog Devices, Inc. Double sampled biquad switched capacitor filter
US5483695A (en) * 1993-05-12 1996-01-09 Csem Centre Suisse D'electronique Et De Microtechnique Intermediate frequency FM receiver using analog oversampling to increase signal bandwidth
US5600680A (en) * 1993-06-01 1997-02-04 Matsushita Electric Industrial Co., Ltd. High frequency receiving apparatus
US5592131A (en) * 1993-06-17 1997-01-07 Canadian Space Agency System and method for modulating a carrier frequency
US5495202A (en) * 1993-06-30 1996-02-27 Hughes Aircraft Company High spectral purity digital waveform synthesizer
US5490173A (en) * 1993-07-02 1996-02-06 Ford Motor Company Multi-stage digital RF translator
US5481570A (en) * 1993-10-20 1996-01-02 At&T Corp. Block radio and adaptive arrays for wireless systems
US5604732A (en) * 1993-12-31 1997-02-18 Samsung Electronics Co., Ltd. Up-link access apparatus in direct sequence code division multiple access system
US5483600A (en) * 1994-02-14 1996-01-09 Aphex Systems, Ltd. Wave dependent compressor
US5483549A (en) * 1994-03-04 1996-01-09 Stanford Telecommunications, Inc. Receiver having for charge-coupled-device based receiver signal processing
US5495500A (en) * 1994-08-09 1996-02-27 Intermec Corporation Homodyne radio architecture for direct sequence spread spectrum data reception
US5604592A (en) * 1994-09-19 1997-02-18 Textron Defense Systems, Division Of Avco Corporation Laser ultrasonics-based material analysis system and method using matched filter processing
US6018262A (en) * 1994-09-30 2000-01-25 Yamaha Corporation CMOS differential amplifier for a delta sigma modulator applicable for an analog-to-digital converter
US5483193A (en) * 1995-03-24 1996-01-09 Ford Motor Company Circuit for demodulating FSK signals
US6014176A (en) * 1995-06-21 2000-01-11 Sony Corporation Automatic phase control apparatus for phase locking the chroma burst of analog and digital video data using a numerically controlled oscillator
US5859878A (en) * 1995-08-31 1999-01-12 Northrop Grumman Corporation Common receive module for a programmable digital radio
US5602847A (en) * 1995-09-27 1997-02-11 Lucent Technologies Inc. Segregated spectrum RF downconverter for digitization systems
US5710998A (en) * 1995-12-19 1998-01-20 Motorola, Inc. Method and apparatus for improved zero intermediate frequency receiver latency
US5705955A (en) * 1995-12-21 1998-01-06 Motorola, Inc. Frequency locked-loop using a microcontroller as a comparator
US5864754A (en) * 1996-02-05 1999-01-26 Hotto; Robert System and method for radio signal reconstruction using signal processor
US6182011B1 (en) * 1996-04-01 2001-01-30 The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration Method and apparatus for determining position using global positioning satellites
US6011435A (en) * 1996-06-12 2000-01-04 Fujitsu Limited Transmission-line loss equalizing circuit
US5710992A (en) * 1996-07-12 1998-01-20 Uniden America Corporation Chain search in a scanning receiver
US6014551A (en) * 1996-07-18 2000-01-11 Nokia Mobile Phones Ltd. Arrangement for transmitting and receiving radio frequency signal at two frequency bands
US5705949A (en) * 1996-09-13 1998-01-06 U.S. Robotics Access Corp. Compensation method for I/Q channel imbalance errors
US6018553A (en) * 1996-09-18 2000-01-25 Wireless Access Multi-level mixer architecture for direct conversion of FSK signals
US6175728B1 (en) * 1997-03-05 2001-01-16 Nec Corporation Direct conversion receiver capable of canceling DC offset voltages
US6169733B1 (en) * 1997-05-12 2001-01-02 Northern Telecom Limited Multiple mode capable radio receiver device
US6178319B1 (en) * 1997-09-26 2001-01-23 Matsushita Electric Industrial Co., Ltd. Microwave mixing circuit and down-converter
US6512785B1 (en) * 1998-02-12 2003-01-28 Yozan Inc. Matched filter bank
US6512798B1 (en) * 1998-03-06 2003-01-28 Hitachi Denshi Kabushiki Kaisha Digital communication system of orthogonal modulation type
US6512544B1 (en) * 1998-06-17 2003-01-28 Foveon, Inc. Storage pixel sensor and array with compression
US7321735B1 (en) * 1998-10-21 2008-01-22 Parkervision, Inc. Optical down-converter using universal frequency translation technology
US7321751B2 (en) * 1999-04-16 2008-01-22 Parkervision, Inc. Method and apparatus for improving dynamic range in a communication system
US6335656B1 (en) * 1999-09-30 2002-01-01 Analog Devices, Inc. Direct conversion receivers and filters adapted for use therein
US20060002491A1 (en) * 2000-11-27 2006-01-05 Broadcom Corporation IF FSK receiver
US6509777B2 (en) * 2001-01-23 2003-01-21 Resonext Communications, Inc. Method and apparatus for reducing DC offset
US7321640B2 (en) * 2002-06-07 2008-01-22 Parkervision, Inc. Active polyphase inverter filter for quadrature signal generation

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140270029A1 (en) * 2013-03-14 2014-09-18 Research & Business Foundation Sungkyunkwan University Apparatus and method for supporting device to device communication
US9647862B2 (en) * 2013-03-14 2017-05-09 Samsung Electronics Co., Ltd. Apparatus and method for supporting device to device communication

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US20140226751A1 (en) 2014-08-14
US6853690B1 (en) 2005-02-08
US20120114078A1 (en) 2012-05-10
US8077797B2 (en) 2011-12-13
US7773688B2 (en) 2010-08-10
US20050100115A1 (en) 2005-05-12
US8571135B2 (en) 2013-10-29

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