JP5970425B2 - Receiving apparatus and receiving method - Google Patents

Description

  The present invention relates to a radio signal receiving apparatus and a receiving method.

  In recent years, with the development of wireless communication systems such as mobile phones and wireless local area networks (LAN), frequency demand has increased. In particular, in the frequency band of several GHz (gigahertz), frequencies are densely allocated, and it is difficult to secure a new frequency band. For this reason, it has been studied to increase the frequency utilization efficiency by using “spatial” and “temporal” among the already assigned frequencies.

  For this realization, a cognitive radio system that is used as communication after grasping an available frequency band that changes depending on the use situation, software radio technology that can flexibly cope with various radio standards, and the like are expected. A required wireless receiver for sensing is required to be able to receive a signal with a low reception level with high accuracy and to detect the absence of another system.

  A conventional wireless receiver uses a bandpass filter before and after the low noise amplifier to remove interference signals outside the desired band. As a band-pass filter of a wireless device in the microwave band, a SAW (SURFACE ACOUSTIC WAVE) filter, a boundary acoustic wave filter, a dielectric filter, and the like are used. SAW filters and boundary acoustic wave filters are used as built-in filters in recent mobile phones because they have a large amount of suppression of signals outside the desired band, and can be mass-produced at a small size and low cost (Non-patent Document 1). Dielectric filters are used in base station receivers that handle relatively broadband wireless signals.

  As a conventional wireless receiver, a direct conversion type receiver that requires a small number of circuit components is used in a portable terminal that receives only one channel (Non-patent Document 2). In a system that receives multiple channels simultaneously, a heterodyne or superheterodyne receiver may be used. In heterodyne and superheterodyne receivers, if there is an interference signal in the image band, it becomes difficult to determine and demodulate the power of the desired signal. (Non-patent Document 3).

However, in cognitive radio systems, software defined radios, and broadband wireless signal sensing devices that support various frequencies, the use of RF bandpass filters limits the frequency band that can be received. . In addition, frequency-variable band-pass filters have been studied. However, there are problems that the variable range is generally narrow and that the insertion loss is larger than that of a frequency-fixed filter. In particular, if the insertion loss of a bandpass filter arranged in front of the low noise amplifier is large, the noise figure of the receiver increases, and a weak signal may not be received and demodulated.
Further, when a band-pass filter is not used, the frequency converter of the radio receiver has a problem that interference signals in the harmonic band interfere with each other because the receiver has sensitivity in a band that is an integral multiple of the local oscillator signal. As a solution to this problem, a method using an FIR filter that makes the frequency that becomes the null point variable has been proposed (Non-Patent Document 4).

Kei Nezu, “Filter using“ Boundary Elastic Wave ”Developed by Murata Manufacturing Co., Ltd.”, Nikkei Electronics, Nikkei BP, May 7, 2007, pp. 12-13 Yoshida, Kato, Tomizawa, Otaka, Tsurumi, “Configuration and Prototype Evaluation of Software Defined Radio Reception System Using Direct Conversion and Low-IF System”, IEICE Transactions 2001/7 vol. J84-B, no. 7, 2001 Tsunehara Tsuneo, “Introduction to CMOS RF Circuit Design-2nd-”, Nikkei Electronics, Nikkei BP, January 28, 2008, pp. 164-174 Rahim Bagheri, Ahmad Mirzaei, Saeed Chehrazi, Mohammad E. Heidari, Minjae Lee, Mohyee Mikhemar, Wai Tang, and Asad A. Abidi, "An 800-MHz-6-GHz Software-Defined WirelessReceiver in 90-nm CMOS", IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 41, NO. 12, pp. 2860-2876, DECEMBER 2006.

  However, when the technique described in Non-Patent Document 4 is used, there is a problem that an increase in the circuit scale is caused if the variable range of the frequency that becomes the null point is widened. As described above, there are various problems in receiving a broadband wireless signal with low noise and high sensitivity.

  In view of the above circumstances, an object of the present invention is to provide a receiving apparatus and a receiving method capable of performing reception with reduced noise and reduced influence of an interference signal while suppressing circuit scale and supporting various frequencies. It is said.

One embodiment of the present invention includes a plurality of sets of a distribution unit that distributes a received radio signal, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit. The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency, and the frequency conversion unit generates a corresponding local oscillation signal generation unit The local oscillation signal thus generated is multiplied by the radio signal distributed by the distributing unit to perform frequency conversion, and the frequency band limiting unit performs predetermined conversion of the radio signal frequency-converted by the corresponding frequency converting unit. And the gain adjusting unit adjusts the gain of the radio signal after frequency conversion passed by the corresponding frequency band limiting unit, and the analog-digital converting unit The radio signal after frequency conversion whose gain is adjusted by the corresponding gain adjustment unit is converted from analog to digital, and the signal processing unit is digitized by the corresponding analog-digital conversion unit after the frequency conversion A signal included in a radio signal is detected, compared with a signal detected by another signal processing unit, an interference signal included in the detected signal is specified, and the local oscillation signal generation unit is a local part having a predetermined frequency. The receiving apparatus generates an oscillating signal or a multiple of a prime number of the local oscillating signal .
Another embodiment of the present invention is a distribution unit that distributes a received radio signal, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a plurality of signal processing units. The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency, and the frequency conversion unit corresponds to the corresponding local oscillation signal generation unit The local oscillation signal generated by the signal is multiplied by the radio signal distributed by the distribution unit to perform frequency conversion, and the frequency band limiting unit performs the frequency conversion by the corresponding frequency conversion unit. The predetermined frequency band, and the gain adjusting unit adjusts the gain of the radio signal after the frequency conversion passed by the corresponding frequency band limiting unit, and the analog digital The conversion unit converts the radio signal after the frequency conversion whose gain is adjusted by the corresponding gain adjustment unit from analog to digital, and the signal processing unit is a frequency conversion digitized by the corresponding analog-digital conversion unit A signal included in the later radio signal is detected, compared with a signal detected by another signal processing unit, an interference signal included in the detected signal is specified, and the signal processing unit detects the detected signal When the difference between the changed signal and the signal detected by another signal processing unit is within a predetermined range, the same signal is determined. The receiving device is characterized by the above.
Another embodiment of the present invention is a distribution unit that distributes a received radio signal, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a plurality of signal processing units. The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency, and the frequency conversion unit corresponds to the corresponding local oscillation signal generation unit The local oscillation signal generated by the signal is multiplied by the radio signal distributed by the distribution unit to perform frequency conversion, and the frequency band limiting unit performs the frequency conversion by the corresponding frequency conversion unit. The predetermined frequency band, and the gain adjusting unit adjusts the gain of the radio signal after the frequency conversion passed by the corresponding frequency band limiting unit, and the analog digital The conversion unit converts the radio signal after the frequency conversion whose gain is adjusted by the corresponding gain adjustment unit from analog to digital, and the signal processing unit is a frequency conversion digitized by the corresponding analog-digital conversion unit A signal included in the later radio signal is detected, compared with a signal detected by the other signal processing unit, an interference signal included in the detected signal is specified, and the signal processing unit detects the detected signal The signal and the signal detected by the other signal processing unit are demodulated by the same modulation method to calculate a correlation value. When the calculated correlation value is higher than a predetermined value, the detected signal is subjected to other signal processing. It is determined that the signal detected by the unit is included.

  One embodiment of the present invention is the above-described receiving device, wherein the signal processing unit uses a radio modulation scheme described in advance corresponding to the detected frequency of the signal in the frequency information stored in advance. Then, the radio signal after the digitized frequency conversion is demodulated.

  One embodiment of the present invention is the above-described receiving device, in which the signal processing unit uses the wireless power described in the frequency information stored in advance corresponding to the detected frequency of the signal. It is characterized in that it is determined whether the detected signal is a desired signal based on one or more of the positions used in the standard or the usage application.

One embodiment of the present invention is a receiving device including a distribution unit, and a plurality of sets of a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit. The distribution unit distributes the received radio signal to the plurality of frequency conversion units, and the local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or an integer multiple of the predetermined frequency. A local oscillation signal of a wave is generated, and the frequency conversion unit multiplies the radio signal distributed by the distribution unit by the local oscillation signal generated by the corresponding local oscillation signal generation unit to perform frequency conversion. The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency converting unit, and the gain adjusting unit corresponds to the corresponding frequency band limiting unit Adjusting the gain of the radio signal after the frequency conversion that has been passed through, the analog-to-digital conversion unit converts the radio signal after the frequency conversion that the corresponding gain adjustment unit has adjusted the gain from analog to digital, The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares the signal detected by the other signal processing unit with the detected signal have a process for identifying an interference signal included in the signal, in the process, the local oscillation signal generating unit, for generating a multiple waves prime local oscillation signal or the local oscillation signal of a predetermined frequency, and wherein the This is the receiving method.
One embodiment of the present invention is a receiving device including a distribution unit, and a plurality of sets of a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit. The distribution unit distributes the received radio signal to the plurality of frequency conversion units, and the local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or an integer multiple of the predetermined frequency. A local oscillation signal of a wave is generated, and the frequency conversion unit multiplies the radio signal distributed by the distribution unit by the local oscillation signal generated by the corresponding local oscillation signal generation unit to perform frequency conversion. The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency converting unit, and the gain adjusting unit corresponds to the corresponding frequency band limiting unit Adjusting the gain of the radio signal after the frequency conversion that has been passed through, the analog-to-digital conversion unit converts the radio signal after the frequency conversion that the corresponding gain adjustment unit has adjusted the gain from analog to digital, The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares the signal detected by the other signal processing unit with the detected signal A process of identifying an interference signal included in the signal, wherein in the process, the signal processing unit changes the amplitude, center frequency, and phase of the detected signal by a predetermined amount, respectively, If the difference from the signal detected by the signal processing unit is within a predetermined range, it is determined that they are the same signal.
One embodiment of the present invention is a receiving device including a distribution unit, and a plurality of sets of a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit. The distribution unit distributes the received radio signal to the plurality of frequency conversion units, and the local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or an integer multiple of the predetermined frequency. A local oscillation signal of a wave is generated, and the frequency conversion unit multiplies the radio signal distributed by the distribution unit by the local oscillation signal generated by the corresponding local oscillation signal generation unit to perform frequency conversion. The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency converting unit, and the gain adjusting unit corresponds to the corresponding frequency band limiting unit Adjusting the gain of the radio signal after the frequency conversion that has been passed through, the analog-to-digital conversion unit converts the radio signal after the frequency conversion that the corresponding gain adjustment unit has adjusted the gain from analog to digital, The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares the signal detected by the other signal processing unit with the detected signal A step of identifying an interference signal included in the signal, wherein the signal processing unit demodulates the detected signal and the signal detected by the other signal processing unit using the same modulation method. Calculating a correlation value, and when the calculated correlation value is higher than a predetermined value, determining that the detected signal includes the signal detected by another signal processing unit. A reception method for the butterflies.

  According to the present invention, it is possible to perform reception with reduced noise and reduced influence of interference signals while suppressing the circuit scale and supporting various frequencies.

It is a schematic block diagram which shows the structure of the receiver in one Embodiment of this invention. It is a figure which shows the example of the signal of the radio frequency band in this embodiment, a local oscillation signal, and the signal of an intermediate | middle frequency band.

  Hereinafter, a receiver (receiving apparatus) according to an embodiment of the present invention will be described with reference to the drawings. The receiver according to the present embodiment frequency-converts a radio frequency (RF) band signal to an intermediate frequency (IF) band (or baseband frequency band) signal. At this time, the receiver of the present embodiment performs a plurality of frequency conversions simultaneously using a plurality of local oscillation signals, and converts the frequency into a plurality of IF band signals. In the IF band signal, a signal in a harmonic frequency band of a local oscillation signal is mixed in addition to a signal in a desired frequency band. Therefore, the receiver compares a plurality of IF band signals to separate a desired band signal and a harmonic interference signal.

  FIG. 1 is a schematic block diagram showing a configuration of a receiver 1 according to an embodiment of the present invention. As shown in the figure, the receiver 1 includes an antenna 11, a wideband LNA (Low Noise Amplifier) 12, a distributor 13, local oscillation signal generators 14-1 to 14-N, and a frequency converter 15-1. 15-N, frequency band limiting units 16-1 to 16-N, gain adjusting units 17-1 to 17-N, analog-digital conversion units (ADC) 18-1 to 18-N, and signal processing unit 19- 1 to 19-N (N is an integer of 2 or more).

The broadband LNA 12 amplifies the RF signal received via the antenna 11 and outputs it to the distribution unit 13. The distributor 13 distributes the RF signal amplified by the wideband LNA 12 and inputs the RF signal to the frequency converters 15-1 to 15-N.
The local oscillation signal generation unit 14-i (i is an integer of 1 or more and N or less) generates a local oscillation signal (LO _i ) having a certain frequency and outputs it to the frequency conversion unit 15-i. The local oscillation signals LO _{1 to} LO _N have different frequencies. For example, the local oscillation signal generators 14-1 to 14 -N have the local oscillation signal L 0 and the local oscillation signal L 0 as the local oscillation signals LO _{1 to} LO _N. , And 2 × L0, 3 × L0,..., M × L0 local oscillation signals are generated.

  The frequency conversion units 15-1 to 15-N frequency-convert radio frequency band RF signals to IF band signals. The local oscillation signal generated by the local oscillation signal generation unit 14-i and the RF signal distributed by the distribution unit 13 are input to the frequency conversion unit 15-i (i is an integer of 1 to N). The frequency conversion unit 15-i multiplies the local oscillation signal input from the local oscillation signal generation unit 14-i by the RF signal input from the distribution unit 13, and converts the signal converted into the IF band by multiplication into a frequency band. The data is output to the restriction unit 16-i.

The frequency band limiting unit 16-i (i is an integer of 1 to N) passes the IF band signal included in the signal output from the frequency conversion unit 15-i and attenuates the signal other than the IF band. It outputs to the gain adjustment unit 17-i.
The gain adjusting unit 17-i (i is an integer of 1 or more and N or less) performs gain adjustment on the IF band signal output from the frequency band limiting unit 16-i. The gain adjusting unit 17-i amplifies the signal level attenuated by the signal processing in the frequency converting unit 15-i and the frequency band limiting unit 16-i to a predetermined power level, and analogizes the amplified signal. -It outputs to the digital conversion part 18-i.

  The analog-digital conversion unit 18-i (i is an integer of 1 to N) performs sampling on the signal output from the gain adjustment unit 17-i at a predetermined sampling frequency, and the intensity of the analog signal Is converted into a digital signal according to the above, and a digital signal of time series data is generated. The analog-digital conversion unit 18-i outputs the generated digital signal of time series data to the signal processing unit 19-i.

  A signal digitized by the analog-digital conversion unit 18-i is input to the signal processing unit 19-i (i is an integer of 1 or more and N). The signal processing units 19-1 to 19-N perform Fourier transform on each input signal to convert the signal into a frequency domain signal, and calculate the frequency information of the IF band signal. The frequency information includes amplitude information and phase information for each frequency. Furthermore, the signal processing units 19-1 to 19-N use the calculated frequency information to compare the signals frequency-converted by the frequency conversion units 15-1 to 15-N, and to convert the signals into IF band signals. Determine whether an interference signal is included.

The IF band signal IF ₁ frequency-converted by the local oscillation signal LO ₁ generated by the local oscillation signal generation unit 14-1 includes not only LO ₁ but also its harmonics 2 × LO ₁ , 3 × LO _1. ,..., N × LO ₁ frequency band signals are mixed. Here, setting LO ₂ = ₂ × LO _1, the signal I F ₂ of IF band frequency-converted by a local oscillation signal LO ₂ local oscillation signal generation unit 14-2 is caused, 2 × _LO 1, 4 × LO ₁ ,..., 2N × LO ₁ and signals in a frequency band that is an even multiple of LO ₁ are mixed. That is, the signal processing unit 19-1, by comparing the frequency information of the signals IF _1, a frequency information of the signal IF ₂ signal processing section 19-2 is to give, even multiple mixed in the signal IF ₁ Wave signals can be determined.

If LO ₃ = 3 × LO ₁ = 3F ₁ is set here, the signal IF ₃ in the IF band frequency-converted by the local oscillation signal LO ₃ generated by the local oscillation signal generation unit 14-3 is 3 _{× LO 1, 6 × LO 1} , and ..., 3 times the LO _1, 6 times, ... the frequency band signal of is mixed. In this way, RF signals are frequency-converted by each of the three local oscillation signals LO ₁ , LO ₂ , and LO ₃ to separate the harmonic signals of 2 times, 3 times, 4 times, 6 times, and 8 times. can do. For this reason, the signal processing unit 19-1 is a signal frequency-converted by each of the three local oscillation signals LO ₁ , LO ₂ , LO ₃ , that is, the signal I F ₁ that is Fourier-transformed by itself, and the signal processing unit 19- 2 is a signal I F ₂ of Fourier transform, by comparing the signal I F ₃ to the signal processing section 19-3 has a Fourier transform twice contained in the signal I F _1, 3-fold, 4-fold, 6 It is possible to detect the mixing of double, eight times,... Harmonic signals.
Similarly, by increasing the parallel number, it is possible to separate interference components due to higher harmonics.

  Each of the local oscillation signal generation units 14-1 to 14-N includes 2 × L0, 3 × L0, 5 × L0, 7 × L0 among a certain local oscillation signal (fundamental frequency) L0 and its integral multiple. If multiples of prime numbers such as 11 × L0,... Are generated, signals in almost all harmonic bands can be covered.

FIG. 2 is a diagram illustrating an example of an RF band signal, a local oscillation signal, and an IF band signal. The operation of the receiver 1 will be described with reference to FIG. As shown in the figure, the RF signal, RF ₁ signal of the frequency band _{F 1,} RF ₂ signal of the frequency band 2F _1, contains RF _N signal of the frequency band NF _1.

The broadband LNA 12 amplifies the RF band signal received via the antenna 11 and outputs the amplified signal to the distribution unit 13. The distributor 13 distributes the RF band signal input from the wideband LNA 12 to the frequency converters 15-1 to 15-N. Local oscillation signal generating unit 14-1 to 14-N, respectively, the frequency band _{F 1,} 2F 1, ..., so the NF ₁ generates a local oscillation signal _LO 1 _{~LO N} of IF band. Each of the frequency conversion units 15-1 to 15-N multiplies the local oscillation signal input from the corresponding local oscillation signal generation unit 14-1 to 14-N and the RF band signal input from the distribution unit 13. into a signal _IF 1 _{~IF N} of IF band was.

As shown in FIG. 2, the frequency conversion section 15-1, the signal IF ₁ obtained by frequency conversion by local oscillation signals LO _1, not only includes signal _{S 11} of the frequency band of LO _1, at its harmonics Signals S ₂₁ and S _{31 in} a frequency band of 2 × LO ₁ and N × LO ₁ are mixed. Further, the signal IF ₁ frequency-converted by the frequency conversion unit 15-2 using the local oscillation signal of LO ₂ = 2 × LO ₁ includes the signal S _{21 in} the frequency band IF of 2 × LO ₁ . Further, the signal IF _N frequency-converted by the frequency conversion unit 15-N with the local oscillation signal of LO ₂ = N × LO ₁ includes the signal S _N1 of the frequency band IF of N × LO ₁ .

Each of the frequency band limiting units 16-i (i is an integer other than 1 or more than N) passes through the IF band of the signal IF _i output from the corresponding frequency converting unit 15-i and attenuates signals other than the IF band. Output to the gain adjuster 17-i. Each of the gain adjusting units 17-i (i is an integer of 1 to N) adjusts the gain of the IF band signal output from the corresponding frequency band limiting unit 16-i, and performs an analog-digital conversion unit. Output to 18-i. Each of the analog-digital conversion units 18-i (i is an integer of 1 or more and N or less) converts the signal IF _i output from the corresponding gain adjustment unit 17-i from an analog to a digital signal, and the signal processing unit 19- output to i.

The signal processing unit 19-i (i is an integer greater than or equal to 1 and lower than N) performs a Fourier transform on the digital signal IF _i to convert it to a frequency domain signal, detects a signal whose received power is equal to or greater than a threshold, and detects the detected signal Frequency information such as frequency, amplitude, and phase information is calculated. Thereby, the signal processing unit 19-1 obtains frequency information of S ₁₁ , S ₁₂ , and S ₁₃ , and the signal processing unit 19-2 obtains frequency information of S ₂₁ , and the signal processing unit 19-N Then, the frequency information of _SN1 is obtained.
The signal processing unit 19-i (i is an integer from 1 to N below) is calculated by the frequency information calculated by itself and the other signal processing unit 19-j (j is an integer from 1 to N below, j ≠ i). It is determined whether the signal IF _i contains a signal other than the desired signal.
In this case, signal processing unit 19-i is the amplitude of the signal S _a which itself detects .DELTA.A, the center frequency [Delta] F, the phase is Δφ changes, the difference between the signal S _m detected by the signal processing unit 19-j when taken, the signal power is below a predetermined value, for example, when the signal power is smaller than the threshold value which is determined substantially 0 and the signal S _a and the signal S _m may be determined to be the same. The amplitude ΔA and the phase Δφ used for the signals of the signal processing unit 19-i and the signal processing unit 19-j are values determined based on previously measured signals.
Or you may judge whether the signal of a harmonic is contained by calculating an autocorrelation. In this case, signal processing unit 19-i receives a signal S _a which itself detects, demodulates assuming a signal S _m which the signal processing unit 19-j detects the same modulation scheme, into digital data. The signal processing unit 19-i includes a digital data demodulated signals S _a, when calculating a correlation value between the digital data obtained by demodulating the signal S _m, the calculated correlation value is higher than the predetermined, signal S _a It is determined that the signals _Sm are the same.
In addition, the signal processing unit 19-i may determine that a signal that exceeds a predetermined threshold for which the received power is determined to be too strong is an interference wave.

Thus, the signal processing section 19-1, the frequency information that it has calculated, compares the frequency information signal processing section 19-2 has been calculated, the signal _{S 12} contained in the signal IF ₁ is the signal IF ₂ It judged to be the same as the signal S ₂₁ contained. Further, the signal processing section 19-1 compares the frequency information that it has calculated, and a frequency information signal processing unit 19-N is calculated, the signal _{S 13} contained in the signal IF ₁ is included in the signal IF _N It is determined that it is the same as the signal _SN1 to be transmitted. Thereby, the signal processing unit 19-1 determines that the signals S ₁₂ and S ₁₃ included in the signal IF ₁ are harmonic signals and are not desired signals.

In the signal processing section 19-2, in some cases the signal _{S 21} is the desired signal. Similarly, in the signal processing unit 19-N, the signal _SN1 may be a desired signal.

The signal processing units 19-1 to 19-N not only determine the frequency and power of the digital signals input from the corresponding analog-digital conversion units 18-1 to 18-N, but also demodulate the detected signals. You may make it perform. For example, the signal processing unit 19-1 removes the signal S ₁₂ and the signal S ₁₃ from the frequency band signal obtained by Fourier transforming the signal IF ₁ and performs demodulation. At this time, the signal processing section 19-1, the amplitude of the signal _{S N1} included signal IF ₂ the amplitude of the signal _{S 21} contained in, and equivalent signal and the generated signal _{S 12} by changing the phase, the signal IF _N and changing the phase to remove the same signal and the signal S ₁₃ generated by. As the amplitude and phase to be changed, values determined based on a signal measured in advance are used in the same manner as the above-described amplitude ΔA and phase Δφ.

In addition, the signal processing units 19-1 to 19-N have frequency usage information describing at least one of the usage, radio power standard, radio modulation scheme, position used in the usage, etc. for each radio frequency band. You may make it have a database which memorizes. Thereby, the signal processing units 19-1 to 19-N can improve the detection accuracy of the RF signal in each radio frequency band or obtain information on the interference signal.
For example, the signal processing units 19-1 to 19-N perform demodulation using a radio modulation scheme described in the frequency use information corresponding to the radio frequency of the detected signal. This radio demodulation method can also be used when calculating the correlation value as described above. Thereby, demodulation can be performed efficiently. The signal processing units 19-1 to 19-N perform digital signals input from the corresponding analog-digital conversion units 18-1 to 18-N by performing demodulation corresponding to the modulation scheme indicated by the frequency use information. May be demodulated.
In addition, the signal processing units 19-1 to 19-N indicate that the use application, the wireless power standard, and the position used in the use application described in the frequency use information corresponding to the radio frequency of the detected signal are the desired signal. If the signal matches the detected signal, it can be determined that the detected signal is the desired wave. Alternatively, the signal processing units 19-1 to 19 -N may use a signal that is not a desired signal depending on a use application corresponding to the radio frequency of the signal that is determined not to be a desired wave, a wireless power standard, and a position used in the use application. Information can be obtained.
Note that the signal processing units 19-1 to 19-N may acquire frequency usage information by inquiring of a server device having a database that stores frequency usage information.

  In the above-described embodiment, the configuration in which the receiver 1 has one antenna 11 has been described. However, the present invention is not limited to this, and a receiver having a plurality of antennas may be used.

In the above-described embodiment, the configuration in which the radio frequency band RF signal is converted into the IF band signal has been described. However, the present invention is not limited thereto, and the radio frequency band RF signal is converted into the baseband signal. It may be.
Each of the local oscillation signal generators 14-1 to 14-N is a combination of a local oscillation signal generator that generates a local oscillation signal having a fundamental frequency and a multiplier that multiplies the generated local oscillation signal by a different multiplication number. You may comprise.

According to the above-described embodiment, the receiver 1 down-converts the received wideband radio signal with the local oscillation signals in a plurality of different frequency bands, which causes a problem when sensing wideband radio frequencies. Isolate band signal leakage. The receiver 1 can determine the radio frequency and power of the desired wave and the interference wave of each signal by comparing the signals down-converted by the local oscillation signals in different frequency bands.
As described above, since it is possible to determine whether or not a signal exists in a predetermined frequency range without performing filtering on the radio signal, loss and noise figure of the frequency variable filter processing in the radio band can be determined. Low noise reception processing can be performed without causing an increase. In addition, since it can be determined whether the detected signal is a signal in a predetermined frequency range or an interference signal outside the predetermined frequency range, the interference signal is detected and separated from the radio signal, and the influence of the interference signal can be determined. Reduced reception processing can be performed.
Therefore, low-noise and high-sensitivity reception of broadband wireless signals can be realized on a small scale as compared with FIR filters. For example, since the FIR filter of the type shown in Fig. 6 of Non-Patent Document 4 is in the BB frequency band, a plurality of capacitors having a large capacitance value are used, so it is difficult to reduce the area. On the other hand, in the present embodiment, a plurality of mixers (frequency conversion units 15-1 to 15-N) and local oscillation signal generation units 14-1 to 14-N (or multipliers) are necessary, but are high. Since it is a frequency (RF) band circuit, it is easy to miniaturize.

  You may make it implement | achieve the function of the receiver 1 in embodiment mentioned above with a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client in that case may be included and a program that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

  The present invention can be used for a receiving device that receives a wideband radio signal, such as a cognitive radio system, a software radio, or a wideband sensing device that supports various frequencies.

1 Receiver 11 Antenna 12 Broadband Low Noise Amplifier (LNA)
13 Distributing units 14-1 to 14-N Local oscillation signal generating units 15-1 to 15-N Frequency converting units 16-1 to 16-N Frequency band limiting units 17-1 to 17-N Gain adjusting units 18-1 to 18-1 18-N Analog-to-digital converter (ADC)
19-1 to 19-N Signal processor

Claims (8)

A distribution unit for distributing received radio signals;
A local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a plurality of sets of signal processing units,
The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency,
The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit,
The gain adjusting unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. Identifying an interfering signal included in the signal ,
The local oscillation signal generation unit generates a local oscillation signal having a predetermined frequency or a multiple of a prime number of the local oscillation signal.
A receiving apparatus.   A distribution unit for distributing received radio signals;
  A local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a plurality of sets of signal processing units,
  The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency,
  The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
  The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit,
  The gain adjusting unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
  The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
  The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. Identifying an interfering signal included in the signal,
  The signal processing unit changes the amplitude, center frequency, and phase of the detected signal by a predetermined amount, and the difference between the changed signal and the signal detected by another signal processing unit is within a predetermined range. If the signal is the same,
  A receiving apparatus.   A distribution unit for distributing received radio signals;
  A local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a plurality of sets of signal processing units,
  The local oscillation signal generation unit generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency,
  The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
  The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit,
  The gain adjusting unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
  The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
  The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. Identifying an interfering signal included in the signal,
  The signal processing unit calculates a correlation value by demodulating the detected signal and the signal detected by another signal processing unit using the same modulation method, and detects when the calculated correlation value is higher than a predetermined value. It is determined that the signal detected by the other signal processing unit is included in the signal.
  A receiving apparatus. The signal processing unit demodulates the radio signal after frequency conversion that has been digitized by using a radio modulation method described in advance corresponding to the detected frequency of the signal in frequency information stored in advance.
Receiving apparatus according to any one of claims 1 to 3, characterized in that. The signal processing unit is based on frequency information stored in advance based on one or more of usages, wireless power standards, or positions used in the usages described corresponding to the detected frequency of the signal. Determining whether the detected signal is a desired signal;
The receiving device according to any one of claims 1 to 4 , wherein the receiving device is configured as described above. A reception method executed by a receiving device including a distribution unit, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit,
The distribution unit distributes the received radio signal to the plurality of frequency conversion units,
The local oscillation signal generator generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency;
The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit;
The gain adjustment unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. have a process for identifying an interference signal included in the signal,
In the process, the local oscillation signal generation unit generates a local oscillation signal having a predetermined frequency or a multiple wave of a prime number of the local oscillation signal.
And a receiving method.   A reception method executed by a receiving device including a distribution unit, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit,
  The distribution unit distributes the received radio signal to the plurality of frequency conversion units,
  The local oscillation signal generator generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency;
  The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
  The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit;
  The gain adjustment unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
  The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
  The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. Identifying an interference signal included in the signal,
  In the process, the signal processing unit changes the amplitude, center frequency, and phase of the detected signal by a predetermined amount, respectively, and the difference between the changed signal and the signal detected by another signal processing unit is When it is within the predetermined range, it is determined that they are the same signal.
  And a receiving method.   A reception method executed by a receiving device including a distribution unit, a local oscillation signal generation unit, a frequency conversion unit, a frequency band limiting unit, a gain adjustment unit, an analog-digital conversion unit, and a signal processing unit,
  The distribution unit distributes the received radio signal to the plurality of frequency conversion units,
  The local oscillation signal generator generates a local oscillation signal of a predetermined frequency or a local oscillation signal of an integer multiple of the predetermined frequency;
  The frequency conversion unit performs frequency conversion by multiplying the local oscillation signal generated by the corresponding local oscillation signal generation unit by the radio signal distributed by the distribution unit,
  The frequency band limiting unit passes a predetermined frequency band of the radio signal frequency-converted by the corresponding frequency conversion unit;
  The gain adjustment unit adjusts the gain of the radio signal after frequency conversion that has been passed by the corresponding frequency band limiting unit,
  The analog-to-digital conversion unit converts the radio signal after frequency conversion in which the corresponding gain adjustment unit has adjusted the gain from analog to digital,
  The signal processing unit detects a signal included in the radio signal after frequency conversion digitized by the corresponding analog-to-digital conversion unit, and compares it with a signal detected by the other signal processing unit. Identifying an interference signal included in the signal,
  In the process, the signal processing unit demodulates the detected signal and the signal detected by another signal processing unit using the same modulation method to calculate a correlation value, and the calculated correlation value is greater than a predetermined value. If high, it is determined that the detected signal includes the signal detected by the other signal processing unit,
  And a receiving method.

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