JP2017028656A - Impulse transmitter, impulse receiver and impulse radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impulse transmitter, an impulse receiver and an impulse radio communication system capable of simplifying a circuit configuration with improved frequency use efficiency.SOLUTION: The impulse transmitter, which transmits a bipolar impulse signal multiplexed by changing phases, includes: a base band signal generator 101 which generates the data signal of a communication clock based on each time slot; a short pulse generator 102 which generates the bipolar short pulse having reverse polarity on the basis of the data signal; and a band pass filter 506 which receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal. The short pulse generator includes a trigger flip flop 902 with a position modulation function, which includes phase control routes SLe-CLh of which number is based on multiplicity for the multiplexing by giving different delays to change the phases of the bipolar short pulse.SELECTED DRAWING: Figure 8

Description

  The embodiments referred to herein relate to impulse transmitters, impulse receivers, and impulse wireless communication systems.

  In recent years, with the explosive increase of Internet users, or the increase in capacity and diversification of contents such as high-definition images, video and audio data, an increase in transmission capacity is also desired in wireless communication.

  As a large-capacity wireless communication system, for example, it is suitable to use a millimeter wave band in which there are few commercial wireless stations and a wide frequency band can be easily secured. In recent years, an impulse radio communication system using RF pulses as a transmission medium has attracted attention as an application to a broadband radio communication system.

  The impulse impulse radio impulse transmitter (impulse transmitter) obtains a high frequency pulse signal by multiplication from a low frequency pulse signal. It becomes unnecessary.

  Therefore, it is possible to simplify and reduce the cost of the configuration of the radio unit as compared with a narrow band transmitter based on a carrier system. For example, as a means for realizing large-capacity radio communication exceeding 10 gigabits per second (10 Gbps), An impulse radio communication system is expected.

  In an impulse radio communication system (impulse radio communication system), data is transmitted by performing ON / OFF modulation and envelope detection for transmitting millimeter wave pulses to data “1” and “0”. Here, the amount of data (transmission speed) that can be transmitted per second is determined by the pass frequency bandwidth of the bandpass filter.

  Furthermore, for example, using a millimeter wave band (30 GHz to 300 GHz) to which several wide frequency bandwidths such as several gigahertz (GHz) to several tens GHz are allocated for wireless communication, several tens of gigabits per second (Gbps) are used. It is suitable for realizing large-capacity communication with a simple system.

  By the way, conventionally, various proposals have been made as a wireless communication system and a communication apparatus using an impulse system.

JP2013-157660A JP 2004-208110 A

  As described above, for example, an impulse radio communication system that performs large-capacity communication using a millimeter wave band has been researched and developed. Further, in recent transmitters of impulse transmitters, for example, so-called bipolar RZ (return zero) that generates a pulse having a polarity opposite to the polarity of “1” immediately before is generated in order to avoid limiting transmission power due to the bright line spectrum. ) Type short pulse generators have appeared.

  However, a problem of the impulse radio communication system including the bipolar RZ type is that the number of transmission bits per frequency bandwidth to be used is small, that is, the frequency utilization efficiency is low.

  That is, in the impulse radio communication system, since ON / OFF modulation is performed, for example, when a frequency bandwidth of 10 GHz is used, only data transmission of about 10 Gbps can be performed.

  In addition, there is a need for a communication system with high frequency utilization efficiency when wireless communication systems are close to each other and mutual interference becomes a problem or when it is required to increase the transmission speed using the same frequency band. .

  By the way, when trying to improve the frequency utilization efficiency in the impulse radio communication system, for example, the circuit configuration of the impulse transmitter may be complicated or increased. That is, in the impulse radio communication system, it is difficult to improve the frequency utilization efficiency without complicating the circuit configuration.

  According to one embodiment, an impulse transmitter for transmitting a multiplexed bipolar impulse signal with varying phases, the impulse having a baseband signal generator, a short pulse generator, and a bandpass filter A transmitter is provided.

  The baseband signal generator generates a data signal in units of time slots of a communication clock, and the short pulse generator generates a bipolar short pulse whose polarity is inverted based on the data signal. The bandpass filter receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal.

  The short pulse generator includes a trigger flip-flop with a position modulation function including a number of phase control paths based on the multiplicity to be multiplexed by changing the phase of the bipolar short pulse by applying different delays.

  According to the disclosed impulse transmitter, impulse receiver, and impulse radio communication system, it is possible to simplify the circuit configuration and further improve the frequency utilization efficiency.

FIG. 1 is a diagram for explaining an example of an impulse radio communication system. FIG. 2 is a diagram for explaining an impulse transmitter in the impulse radio communication system. FIG. 3 is a diagram (part 1) for describing a bipolar RZ type impulse transmitter. FIG. 4 is a diagram (part 2) for explaining a bipolar RZ type impulse transmitter. FIG. 5 is a diagram (part 3) for explaining the bipolar RZ type impulse transmitter. FIG. 6 is a diagram illustrating an example of a short pulse generator in an impulse transmitter as a related technique. FIG. 7 is a block diagram illustrating an example of an impulse receiver that receives a signal from the impulse transmitter illustrated in FIG. 6. FIG. 8 is a diagram showing an example of a short pulse generator in the first embodiment of the impulse transmitter. FIG. 9 is a circuit diagram showing an example of a selector in the short pulse generator shown in FIG. FIG. 10 is a diagram for explaining the operation of the selector shown in FIG. FIG. 11 is a timing chart for explaining the operation of the short pulse generator shown in FIG. FIG. 12 is a timing chart for explaining the operation of the impulse transmitter according to the first embodiment. FIG. 13 is a block diagram illustrating an example of an impulse receiver that receives a signal from the impulse transmitter according to the first embodiment. FIG. 14 is a timing chart showing an example of signals in each part of the impulse receiver shown in FIG. FIG. 15 is a diagram showing an example of a short pulse generator in the second embodiment of the impulse transmitter. FIG. 16 is a diagram for explaining an example of an amplitude control circuit applied to the impulse transmitter shown in FIG. FIG. 17 is a diagram for explaining another example of the amplitude control circuit applied to the impulse transmitter shown in FIG. FIG. 18 is a diagram for explaining a modification of the impulse transmitter according to the second embodiment.

  First, before describing this embodiment in detail, an example of an impulse radio communication system, an impulse transmitter and an impulse receiver as related techniques, and problems thereof will be described with reference to FIGS.

  FIG. 1 is a diagram for explaining an example of an impulse radio communication system, FIG. 1 (a) is a block diagram showing an example of an impulse radio communication system, and FIG. 1 (b) is a diagram of a bandpass filter. It is a figure for demonstrating a pass frequency band.

  As shown in FIG. 1A, the impulse radio communication system (impulse radio communication system) includes an impulse transmitter Tx and an impulse receiver Rx. The impulse transmitter Tx includes a baseband signal generator 101, a short pulse generator 102, a bandpass filter 103, a transmission amplifier 104, and a transmission antenna 105.

  The baseband signal generator 101 generates a data signal for each time slot of the communication clock and outputs the data signal to the short pulse generator 102. Here, for example, the value of “1” is a high level “H”, and the value of “0” is a low level “L”.

  The communication clock is, for example, 5 GHz. In this case, the communication speed of the data signal is, for example, 5 gigabits / second (Gbps). For example, the short pulse generator 102 generates a short pulse when the data signal becomes high level in a time slot. The band pass filter 103 performs filtering that allows only a predetermined pass frequency band to pass through the short pulse, and outputs, for example, a millimeter wave pulse.

  In FIG. 1B, reference numeral 131 indicates a frequency characteristic (short pulse characteristic) of a short pulse, and 132 indicates a pass frequency band of the bandpass filter 103. As shown in FIG. 1B, the millimeter wave pulse output from the bandpass filter 103 has frequency components only in the pass frequency band 132 portion of the short pulse characteristic 131.

  By the way, for example, in UWB (Ultra Wide Band), the usable frequency band is limited, and the band pass filter 103 is used so as to satisfy the limitation of the frequency band. In the pass frequency band 132, for example, the pass lower limit frequency f1 is 80 GHz, the pass upper limit frequency f2 is 90 GHz, and the pass frequency bandwidth is f2-f1 = 90-80 = 10 GHz.

  FIG. 2 is a diagram for explaining an impulse transmitter in an impulse radio communication system. FIG. 2A shows a short pulse generator (unipolar RZ (return zero) type short pulse generator) 102 and a bandpass filter. The signal generated at 103 is shown.

  2B shows the filter characteristics (pass frequency band) of the bandpass filter 103, and FIG. 2C shows the emission line spectrum when the unipolar RZ short pulse generator 102 is used.

  Here, in FIG.2 (c), a horizontal axis shows a frequency (GHz) and a vertical axis | shaft shows electric power spectral density (dBm / Hz). FIG. 2C shows a case where fc is 83.5 GHz and Bw = 5 GHz (81-86 GHz). 2A to 2C, fc indicates the center frequency in the pass frequency band of the band pass filter 103, and Bw indicates, for example, the pass bandwidth where the power is reduced by 3 dB.

As shown in FIG. 2A, the short pulse generator (unipolar RZ type short pulse generator) 102 generates, for example, a positive pulse with a narrow width. This narrow pulse includes a wide range of frequency components including high frequency components, and, for example, a millimeter wave pulse is generated by passing through the band pass filter 103. That is, as shown in FIG. 2B, the millimeter wave pulse that has passed through the bandpass filter 103 becomes a vibration signal (pulse signal) having a width Bw ⁻¹ that vibrates at a frequency fc.

  Referring again to FIG. 1A, the output of the bandpass filter 103 is input to the transmission amplifier 104, for example, a millimeter wave pulse is amplified, and the transmission signal is wirelessly transmitted via the transmission antenna 105. . The transmission signal represents “1” or “0” data depending on the presence / absence (ON / OFF) of a millimeter wave pulse. At this time, as shown in FIG. 2C, the transmission signal (power spectral density) includes, for example, the bright line spectrum Sb.

  As shown in FIG. 1A, the impulse receiver Rx includes a reception antenna 121, a reception amplifier 122, a detector 123, a limit amplifier 124, and a baseband signal regenerator 125.

  The reception amplifier 122 amplifies the reception signal received wirelessly via the reception antenna 121 and outputs the amplified signal to the detector 123. The detector 123 detects the envelope of the reception signal (millimeter wave pulse) amplified by the reception amplifier 122 and outputs it to the limit amplifier 124.

  The limit amplifier 124 amplifies the signal detected by the detector 123 and outputs the amplified signal to the baseband signal regenerator 125. Then, the baseband signal regenerator 125 receives the signal amplified by the limit amplifier 124 and reproduces, for example, 5 Gbps received data.

  As described above, the impulse radio communication system can be used for ultra-wideband radio communication including, for example, a microwave band, a quasi-millimeter wave band, and UWB, as well as the millimeter wave band.

  Since this impulse radio communication system does not require an oscillator or a mixer and the configuration of the RF unit is simple and low in cost as compared with a radio communication system of a narrow band communication system, for example, in the millimeter wave band where a wide band can be used, 10 Gbps Realization of wideband wireless communication exceeding that is expected.

  Here, assuming that the frequency bandwidth allocated to the impulse radio communication system is Bmax, the maximum communication speed Bmax can be obtained when the pass frequency bandwidth Bbpf of the bandpass filter 103 is equal to Bmax.

  For example, when the frequency bandwidth Bmax is 10 GHz, as shown in FIG. 1B, the pass frequency bandwidth Bbpf of the bandpass filter 103 is f2-f1 = 90-80 = 10 GHz, and data signal communication The speed will be 10 Gbps.

  By the way, in many wireless communication systems, for example, the signal strength per unit frequency (power spectral density) is defined by laws and regulations such as a signal strength of 0 dBm per frequency of 1 dBm (= 1 mW / MHz). .

  Therefore, as shown in FIG. 2C, for example, the transmission signal (power spectral density) includes the bright line spectrum Sb. When the signal intensity of the bright line spectrum Sb is limited to the power spectral density, a situation occurs in which the average power in the entire frequency band cannot be increased.

  Specifically, for example, when the assigned frequency band Bmax is 10 GHz (= 10000 MHz) and the transmission spectrum intensity is constant within the frequency band, an output of 1 (mW / MHz) × 10000 (MHz) = 10 W is obtained. It becomes possible.

  However, if the transmission signal includes the bright line spectrum Sb of 1 mW / MHz, the bright line spectrum Sb is also limited by the signal intensity based on, for example, the Radio Law, so that only small power is allowed.

  In general, in order to transmit a signal over a long distance without error, it is preferable to secure a signal intensity margin (S / N ratio) against noise or the like by maximizing the spectrum power in all frequency bands. However, when the transmission power is limited by the bright line spectrum Sb, it becomes difficult to secure a sufficient S / N ratio.

  As described above, when the transmission power is limited by the bright line spectrum Sb, high-quality wireless communication is disadvantageous at a long distance. Therefore, it is required to realize an impulse radio communication system that does not generate the bright line spectrum Sb. Therefore, a bipolar return zero (RZ) type impulse radio communication system that does not include the bright line spectrum Sb in the transmission signal and is suitable for long-distance high-quality radio communication has been proposed.

  3 to 5 are diagrams for explaining a bipolar RZ type impulse transmitter. Here, FIG. 3A is a block diagram showing an example of a short pulse generator 102 used in a bipolar RZ type impulse transmitter (B-RZ impulse transmitter). Shown with generation filter 506 and pulse (wideband) amplifier 507.

  The pulse generation filter 506 corresponds to the band pass filter 103, and the pulse amplifier 507 corresponds to the transmission amplifier 104. FIG. 3B shows a circuit diagram of an example of the trigger flip-flop (T-FF) 504 shown in FIG.

  4A shows a positive pulse generated by the short pulse generator 102 and a positive millimeter wave pulse (impulse signal) generated via the pulse generation filter 506 (bandpass filter 103). ) Example. Further, FIG. 4B shows an example of the negative polarity pulse generated by the short pulse generator 102 and the negative polarity millimeter wave pulse generated via the pulse generation filter 506.

  FIG. 5A is a time chart for explaining operations of the short pulse generator 102 and the pulse generation filter 506 shown in FIG. 3A, and FIG. 5B is a bipolar RZ short pulse. It is a figure which shows an emission line spectrum (notch) at the time of using the generator 102. FIG.

  In FIG. 5B, the horizontal axis indicates the frequency (GHz), and the vertical axis indicates the power spectrum density (dBm / Hz). FIG. 5B shows a case where fc is 83.5 GHz and Bw = 5 GHz (81-86 GHz).

  As shown in FIG. 3A, the bipolar RZ short pulse generator 102 includes input buffers 501 and 502, an NRZ-RZ converter 503, a trigger flip-flop (T-FF) 504, edge shaping ( And a shaping) circuit 505.

  The edge shaping circuit 505 includes, for example, an even number of inverters connected in series, and the output signal edge-shaped by the edge shaping circuit 505 is input to the pulse generation filter 506 (103).

  The data signal A is a non-return zero signal, the input buffer 501 buffers the non-return zero signal A, and the clock buffer 502 buffers the clock signal Clock.

  An NRZ (Non-Return to Zero) -RZ (Return to Zero) conversion unit 503 converts a non-return zero signal A into a return zero signal B. Specifically, the NRZ-RZ conversion unit 503 is, for example, a logical product (AND) circuit, takes a logical product of the non-return zero signal A and the clock signal CLK, and outputs the logical product signal as a return zero signal B. .

  The T-FF 504 is realized by, for example, a master-slave type flip-flop circuit using the return zero signal B as a transfer gate signal, as shown in FIG. That is, the T-FF 504 includes a master latch by inverters 602 and 603 whose inputs and outputs are cross-connected, a slave latch by inverters 605 and 606, and an inverter 607 provided in the feedback path of the output of the slave latch.

  The T-FF 504 further includes transfer gates 601 and 604 formed of transistors. The transfer gate 601 is provided in a path for feeding back the output of the slave latch to the master latch via the inverter 607, and the gate 604 is provided between the output of the master latch and the input of the slave latch.

  The conduction state of transfer gate 601 is controlled by a return zero signal B, and the conduction state of transfer gate 604 is controlled by an inverted signal / B of return zero signal B. As a result, the T-FF 504 functions as a frequency divider for the return zero signal B that inverts the output signal C every time the return zero signal B changes by one cycle.

  For example, every time the return zero signal B changes by one cycle such as “H” → “L” → “H”, the logic level of the output signal C is inverted. That is, as shown in FIG. 5A, the output signal C is logically inverted in synchronization with the rising edge of the return zero signal B.

  The edge shaping circuit 505 generates a signal in which the rising edge and the falling edge of the output signal C of the T-FF 504 are steep, and outputs the signal to the pulse generation filter 506. Here, the signal in which the output signal C is steep becomes a signal having a short rise time and fall time, and a signal including a spectrum up to a higher frequency.

  As described above, the edge shaping circuit 505 can be realized by, for example, an even number of inverters connected in series. Further, the edge shaping circuit 505 may be further provided with an inductor for giving peaking so that a steeper edge can be obtained.

  An inverter connects a p-channel MOS transistor and an n-channel MOS transistor in series between power supplies, applies an input signal to the gates of the two transistors, and obtains an inverted signal from a connection node between the pMOS transistor and the nMOS transistor It is realized with. The same applies to inverters used in other parts.

  The pulse generation filter 506 is a high-pass filter or a band-pass filter. The pulse generation filter 506 removes the low frequency component of the output signal of the edge shaping circuit 505 to determine whether or not there is a pulse corresponding to the value of the data signal A (value of data “1”). A signal D in which negative pulses are alternately generated is output. Here, as the pulse generation filter 506, for example, capacitor elements connected in series can be applied.

  The pulse amplifier 507 (104) is a wideband amplifier or a distributed amplifier, amplifies the output signal D of the pulse generation filter 506, and outputs the amplified signal to the transmission antenna 105 of FIG. Note that the edge shaping circuit 505 may be deleted when the edge of the signal C is sufficiently steep. Further, if the magnitude of the signal D is sufficient, the pulse amplifier 507 can be deleted.

  The bipolar short pulse output from the short pulse generator 102 to the bandpass filter 103 (pulse generation filter 506) is the presence or absence of a pulse corresponding to the value of the data signal, and alternately generates a positive pulse and a negative pulse. Pulse.

  In the bipolar short pulse, for example, a positive pulse or a negative pulse is generated when the value of the data signal is “1”, and becomes a reference voltage when the value of the data signal is “0”. The positive pulse is a pulse having a positive voltage with respect to the reference voltage, and the negative pulse is a pulse having a negative voltage with respect to the reference voltage. That is, the bipolar short pulse becomes a pulse having a polarity opposite to that of the immediately preceding pulse.

  Here, as is clear from the comparison between FIG. 5B and FIG. 2C described above, the emission line spectrum Sb when the unipolar RZ short pulse in FIG. 2C is used is shown in FIG. As described above, the notch Sn is obtained by using a bipolar RZ short pulse. As a result, the signal intensity of the bright line spectrum Sb is not restricted by the power spectral density (transmission signal), and the average power in all frequency bands can be increased.

  As described above, when the bipolar short pulse is used, a notch (concave portion) is generated at a frequency equal to an integral multiple of the communication speed (10 Gbps), and the power spectral density is reduced. Therefore, the maximum value of the signal strength per unit frequency can be reduced as compared with the case where unipolar short pulses are used, and transmission power can be easily secured, which is advantageous for long-distance / high-quality communication.

  By the way, the impulse radio communication system including the unipolar RZ system and the bipolar RZ system has a problem that the number of transmission bits per frequency bandwidth to be used is small, that is, the frequency utilization efficiency is low.

  That is, in the impulse radio communication, since ON / OFF modulation is performed, when a frequency bandwidth of 10 GHz is used, only data transmission of 10 Gbps can be performed. In addition, for example, when wireless communication systems are close to each other and mutual interference becomes a problem, and there is a demand to increase the transmission speed using the same frequency band, a communication system with high frequency utilization efficiency is required.

  For example, in order to improve the frequency utilization efficiency of a wireless communication device, it is considered that a method of putting information of a plurality of bits on one symbol, so-called multi-value, is effective. Therefore, in the case of pulse transmission, pulse position modulation (PPM) that transmits information by changing the appearance position of a pulse has been researched and developed.

  That is, when performing pulse position modulation in an impulse radio communication system, for example, one pulse (impulse) may be arranged within one period, and the position (phase) where the pulse is arranged may be changed according to transmission data. .

  FIG. 6 is a diagram showing an example of a short pulse generator in an impulse transmitter as a related technique, in which the phase in which a pulse is arranged is changed within one period (−π, −π / 2, reference (0), + π / 2, + π) is an example of transmitting 2-bit data (an example of multiplicity of “2”). For example, it is preferable that a quarter period (for example, 3 ps) in one period (for example, 12 ps) corresponds to a phase (arrangement) of π / 2.

  FIG. 6A is a block diagram showing an example of the short pulse generator 102 used in the B-RZ impulse transmitter. The short pulse generator 102 is connected to the pulse generation filter 506 (103) and the pulse ( Shown with a wideband amplifier 507 (104). FIG. 6B shows a circuit diagram of an example of the T-FF (trigger flip-flop with position modulation function) 504 shown in FIG.

  As is clear from the comparison between FIG. 6A and FIG. 3A described above, the short pulse generator 102 according to the related art includes a selector 701, a clock buffer 502, a T-FF 702, and edge shaping (shaping). ) Circuit 505.

  The clock buffer 502, the edge shaping circuit 505, the pulse generation filter 506, and the pulse amplifier 507 are the same as those described with reference to FIG.

  The selector 701 generates five selection signals p, q, r, s, and t based on the 2-bit data pattern of the serial transmission data Data and the divide-by-2 signal M of the communication clock Clock.

  That is, when the multiplicity is “2”, five phase control paths (signal paths) SLp˜ are used to generate signals having phases of −π, −π / 2, reference (0), + π / 2, + π. SLt is provided, and one of them can be selected by five selection signals p, q, r, s, and t.

Note that the number of phase control paths (selection signals) in the related art impulse transmitter (the variable delay unit 720 of the T-FF 702 of the short pulse generator 102) is greater than 2 ^N when N is the multiplicity ( 2 ^N +1 or more).

  As described above, one of the selection signals p, q, r, s, and t is a signal that is selectively turned on (high level “H”) and the rest is turned off (low level “L”). . As the frequency-divided signal M, for example, a signal generated as the output of the inverter 712 of the T-FF 702 shown in FIG. 6B can be used.

  The T-FF 702 has a circuit configuration as shown in FIG. 6B, for example, and outputs a divided signal obtained by dividing the communication clock clock by two. The changing edge of the frequency-divided signal changes in phase by π / 2 (for example, 3 ps) according to the selection signals p, q, r, s, and t.

  The T-FF 702 has a master latch by inverters 712 and 713 whose inputs and outputs are cross-connected, a slave latch including inverters 715 and 716, and an inverter 717 provided in a feedback path of the output of the slave latch.

  The T-FF 702 further includes transfer gates 711 and 714. The transfer gate 711 is provided in a path for feeding back the output of the slave latch to the master latch via the inverter 717, and the transfer gate 714 is provided between the output of the master latch and the input of the slave latch.

  The transfer gate 711 is controlled to be conductive by the clock signal Clock, and the transfer gate 714 is controlled by the inverted signal / Clock of the clock signal Clock.

  The T-FF 702 further includes a variable delay unit 720 connected between the output of the inverter 715 and the input of the inverter 716 (the output node of the T-FF 702 with a position modulation function) in the slave latch.

  The variable delay unit 720 includes first to fifth phase control paths SLp to SLt connected in parallel between the output of the inverter 715 and the input of the inverter 716. Here, the first phase control path SLp has only the transfer gate 721, and the selection signal p is input to the gate of the transfer gate 921.

  Second phase control path SLq has transfer gates 722 and 724 and buffer 723 connected in series, and selection signal q is input to the gates of transfer gates 722 and 724. The third phase control path SLr includes transfer gates 725 and 727 connected in series and a buffer row 726 connecting two buffers, and a selection signal q is input to the gates of the transfer gates 725 and 727. The

  The fourth phase control path SLs includes transfer gates 728 and 730 connected in series, and a buffer row 729 in which three buffers are connected. The selection signal s is input to the gates of the transfer gates 728 and 730. .

  The fifth phase control path SLt includes transfer gates 731 and 733 connected in series and a buffer row 732 in which four buffers are connected. The selection signal t is input to the gates of the transfer gates 731 and 733. . Here, the buffer 723 and the buffer rows 726, 729, and 732 differ in the number of buffers to be connected, and the delay amount increases according to the number of buffers.

  Thereby, for example, when the output of the third phase control path SLr is set to the reference (0), the phase at the output of the first phase control path SLp is set to −π, and the phase at the output of the second phase control path SLq is set to It can be set to −π / 2.

  Further, for example, when the output of the third phase control path SLr is set to the reference (0), the phase at the output of the fourth phase control path SLs is set to + π / 2, and the phase at the output of the fifth phase control path SLt is set to It can be set to + π.

  Thus, in the related art impulse transmitter shown in FIG. 6, for example, the variable delay unit 720 in the T-FF 702 with a position modulation function includes the first to fifth phase control paths SLp to SLt.

  Further, in order to control the buffers in the five phase control paths SLp to SLt, the selector 701 also generates five selection signals p to t. For this reason, the circuit configuration increases and becomes complicated.

  FIG. 7 is a block diagram illustrating an example of an impulse receiver that receives a signal from the impulse transmitter illustrated in FIG. 6. An impulse receiver that receives a bipolar impulse signal that is multiplexed by changing the phase and that is output from the impulse transmitter according to the related art described with reference to FIG. 6 has the configuration shown in FIG. 7, for example.

  As shown in FIG. 7, the impulse receiver includes a reception antenna 121, a reception amplifier 122, a detector 123, a limit amplifier 124, and a baseband signal regenerator 125.

  The detector 123 includes a unipolar short pulse generator 801, a band pass filter 802, a first mixer (mixer) 803A, a second mixer (mixer) 803B, and a π / 2 phase shifter 804. The unipolar short pulse generator 801 generates a short pulse every half cycle of the frequency signal (divided by 2 signal) obtained by dividing the communication clock Clock by the multiplicity (here, “2”).

  That is, the unipolar short pulse generator 801 generates a short pulse of a local oscillation signal having a center frequency (for example, 83.5 GHz) of the pass band of the bandpass filter 103 of the impulse transmitter, for example.

  The bandpass filter 802 has the same pass characteristics as the bandpass filter 103 of the transmitter, receives the output signal of the bipolar short pulse generator 805, is an oscillation signal having the same frequency as the vibration signal, and has a short envelope. A pulse signal corresponding to the pulse signal is generated.

  The first mixer 803A performs detection by mixing the output signal of the reception amplifier 122 with the pulse signal output from the bandpass filter 802. The second mixer 803B shifts the phase of the pulse signal output from the bandpass filter 802 by π / 2 by the π / 2 phase shifter 804 to the output signal of the reception amplifier 122, and mixes the phase-shifted signal. And detect. This provides an intermediate frequency (IF) signal.

  The limit amplifier 124 includes a first amplifier 124A that amplifies the output of the first mixer 803A, and a second amplifier 124B that amplifies the output of the second mixer 803B. Here, the local oscillation signals mixed by the first mixer 803A and the second mixer 803B are out of phase by π / 2 (for example, 3 ps), and the IF signal (Q signal) is output from the first amplifier 124A. An IF signal (I signal) is output from the second amplifier 124B.

  The baseband signal regenerator 125 includes an analog-to-digital converter (ADC) 851, a phase detector 852, and a data regenerator 853. The ADC 851 converts the IF signal (Q) and the IF signal (I) into digital data.

  The phase detector 852 detects the phase of the received impulse signal from the digital data of the IF signal (Q) and the IF signal (I). The data reproducing unit 853 reproduces data from the detected phase and the received clock phase.

  As described above, the impulse transmitter of the related art described with reference to FIG. 6 can reproduce transmission data by applying a unipolar short pulse generator 801 as shown in FIG. 7 as an impulse receiver. Yes, but the circuit scale is large and complicated.

  That is, the impulse radio communication system according to FIG. 6 and FIG. 7 can multiplex transmission data by changing the phase in which pulses are arranged within one period, but the complexity of the impulse transmitter increases in circuit scale. There is a problem of becoming.

  Hereinafter, embodiments of an impulse transmitter, an impulse receiver, and an impulse radio communication system will be described in detail with reference to the accompanying drawings. FIG. 8 is a diagram showing an example of a short pulse generator in the first embodiment of the impulse transmitter, in which the phase in which pulses are arranged is changed within one period (−π / 2, reference (0), + π / 2). , + Π), and an example of transmitting 2-bit data (an example where the multiplicity is “2”) is shown. For example, it is preferable that a quarter period (for example, 3 ps) in one period (for example, 12 ps) corresponds to a phase (arrangement) of π / 2.

  Here, FIG. 8A is a block diagram showing an example of the short pulse generator 102 used in the B-RZ impulse transmitter. The short pulse generator 102 includes a pulse generation filter 506 (103) and a pulse amplifier. 507 (transmission amplifier 104). FIG. 8B shows a circuit diagram of an example of the T-FF (trigger flip-flop with position modulation function) 504 shown in FIG.

  As shown in FIG. 8A, the short pulse generator 102 of the first embodiment includes a selector 901, a clock buffer 502, a T-FF 902, and an edge shaping (shaping) circuit 505.

  Here, the edge shaping circuit 505 includes, for example, an even number of inverters connected in series, and the output signal edge-formed by the edge shaping circuit 505 is input to the pulse generation filter 506 (103). The clock buffer 502, the pulse generation filter 506, and the pulse (broadband) amplifier 507 are the same as those described with reference to FIG. 3, for example, and description thereof is omitted.

  The selector 901 generates four selection signals e, f, g, and h in accordance with the 2-bit data pattern of the serial transmission data Data. Here, one of the four selection signals e, f, g, and h is selectively turned on (high level “H”), and the remaining three are turned off (low level “L”).

  As is clear from the comparison between FIG. 8A and FIG. 6A described above, the selector 901 of the first embodiment transmits the signal without using the frequency-divided signal M of the communication clock Clock. Selection signals e, f, g, and h are generated from the data Data. An example of the selector 901 will be described in detail later with reference to FIG.

  The T-FF 902 has a circuit configuration as shown in FIG. 8B, for example, and outputs a frequency-divided signal obtained by dividing the communication clock clock by two (C). The change edge of the frequency-divided signal changes in phase by π / 2 (for example, 3 ps) according to the selection signals e, f, g, and h.

  The T-FF 902 includes a master latch by inverters 912 and 913 whose inputs and outputs are cross-connected, a slave latch by inverters 915 and 916, and an inverter 917 provided in an output feedback path of the slave latch.

  The T-FF 902 further includes transfer gates 911 and 914. The transfer gate 911 is inserted in a path for feeding back the output of the slave latch to the master latch via the inverter 917. The transfer gate 914 is inserted between the output of the master latch and the input of the slave latch.

  Here, the conduction state of the transfer gate 911 is controlled by the clock signal Clock, and the conduction state of the transfer gate 914 is controlled by the inverted signal / Clock of the clock signal Clock.

  The T-FF 902 further includes a variable delay unit 920 provided between the output of the inverter 915 and the input of the inverter 916 (the output node of the T-FF 902 with position modulation function) in the slave latch.

  Variable delay section 920 has first to fourth phase control paths SLe to SLh connected in parallel between the output of inverter 915 and the input of inverter 916. The first phase control path SLe has only the transfer gate 921, and the selection signal e is input to the gate of the transfer gate 921.

  The second phase control path SLf has a transfer gate 922 and a buffer 923 connected in series, and the selection signal f is input to the gate of the transfer gate 922. The third phase control path SLg has a transfer gate 924 connected in series and a buffer row 925 in which two buffers are connected. The selection signal g is input to the gate of the transfer gate 924.

  The fourth phase control path SLg includes a transfer gate 926 connected in series and a buffer row 927 in which three buffers are connected. The selection signal h is input to the gate of the transfer gate 926. Here, the number of buffers connected to the buffers 923 and 925 and 927 is different, and the delay amount increases according to the number of buffers.

  Thereby, for example, when the output of the second phase control path SLf is set to the reference (0), the output phase of the first phase control path SLe is −π / 2, and the output phase of the third phase control path SLg is + π / 2. The output phase of the fourth phase control path SLh can be set to + π.

  Here, for example, when the center frequency of the pass frequency band of the pulse generation filter 506 (bandpass filter 103) is fc and the period T is T = 1 / fc, the phase difference “π / 2 ”(difference in delay time) is set to T / 4 (for example, about 3 ps).

  For example, when the output of the second phase control path SLf is used as a reference, the output of the first phase control path SLe is set to −3 ps (−T / 4: −π / 2), and the output of the third phase control path SLg The output is set to +3 ps (+ T / 4: + π / 2).

  In the variable delay unit 920, the output of the first phase control path SLe is selected for the selection signal e of the selector 901, and the output of the second phase control path SLf is selected for f. Further, the output of the third phase control path SLg is selected for the selection signal g, and the output of the fourth phase control path SLg is selected for h.

  As is apparent from a comparison between FIG. 8A and FIG. 6A described above, the short pulse generator 102 of the first embodiment is the same as the short pulse generator of the related art described with reference to FIG. In comparison, the number of phase control paths in the variable delay unit 920 can be reduced from five to four.

  That is, when the multiplicity is “2”, four phase control paths SLe to SLh are provided to generate a signal having a phase of −π / 2, reference (0), + π / 2, + π, and one of them is provided. Can be selected by four selection signals e, f, g, and h.

Generalizing this, the number of phase control paths (selection signals) in the impulse transmitter of the first embodiment (the variable delay unit 920 of the T-FF 902 of the short pulse generator 102) is as follows. 2 ^N.

  FIG. 9 is a circuit diagram showing an example of a selector in the short pulse generator shown in FIG. As shown in FIG. 9, the selector 901 includes a 1: 2 serial / parallel conversion circuit 940 and four AND gates 951 to 954. Here, one input of the AND gate 951 is an inverted input, both inputs of the AND gate 952 are inverted inputs, and the other input of the AND gate 953 is an inverted input.

  The serial / parallel conversion circuit 940 converts, for example, two bits of transmission data Data, which is a serial signal, into parallel data. The outputs of the serial / parallel conversion circuit 940 are respectively input to AND gates 951 to 954, so that either one is “H” and the remaining is “L” corresponding to 2 bits of the transmission data Data. The following four selection signals e, f, g, and h are generated.

  Note that the selector 901 in the short pulse generator 102 of the first embodiment also reduces the selection signal from 5 to 4 compared to the selector 701 of the short pulse generator of the related art described with reference to FIG. Therefore, the circuit configuration is also simplified.

  FIG. 10 is a diagram for explaining the operation of the selector shown in FIG. 9, and FIG. 10 (a) shows selection signals e, f, g corresponding to 2-bit data (2-bit data) of transmission data Data. , H and the impulse signal generated by the pulse generation filter 506 (103). FIG. 10B shows the phase relationship for each value of 2-bit data.

  Here, E (0, 1) is assigned to the selection signal e (that is, only e is “H” and f, g, h are “L”), and F (0, 0) is assigned to the selection signal f. ), G (1, 0) is assigned to the selection signal g, and H (1, 1) is assigned to the selection signal h.

  As shown in FIGS. 10A and 10B, for example, when the 2-bit data of the transmission data Data is (0, 0), the selection signal f becomes “H” as a reference. When the 2-bit data is (0, 1), the selection signal e becomes “H”, and the delay is advanced by −Tc / 4 (−π / 2), that is, π / 2.

  Further, when the 2-bit data is (1, 0), the selection signal g is “H”, the delay is + Tc / 4 (+ π / 2), that is, a delay of π / 2, and ( In the case of (1, 1), the selection signal h becomes “H”, and the delay is + Tc / 2 (+ π), that is, a delay of π. In FIG. 10A, the waveform of the impulse signal in the case of the reference is shown in the upper right (first quadrant), and in the other three (second to fourth quadrant), the waveform of the reference impulse signal is indicated by a broken line. Show.

  As shown in FIG. 10B, the transmission signal output from the impulse transmitter (short pulse generator) of this embodiment is similar to, for example, quadrature phase shift keying (QPSK). It will show the relationship. Accordingly, for example, quadrature demodulation by coherent detection using a known QPSK demodulation technique is possible, and reception sensitivity can be increased.

  However, as an impulse receiver that receives a transmission signal by the impulse transmitter of this embodiment and reproduces transmission data, for example, as will be described later with reference to FIG. 13, a short pulse generator for reception is used. A bipolar short pulse generator is used.

  In the above, the assignments shown in FIGS. 10 (a) and 10 (b) are merely examples and, of course, are not limited thereto. In addition, the phase (position) at which a pulse (impulse) is arranged within one period is not limited to four shifted by π / 2, and the configuration of the serial / parallel conversion circuit 940 and the like changes accordingly. Needless to say.

  FIG. 11 is a timing chart for explaining the operation of the short pulse generator shown in FIG. As illustrated in FIG. 11, the output signal C of the T-FF 902 changes, for example, every cycle of the clock signal Clock.

  Here, the time from the falling edge of the clock signal Clock to the changing edge of the output signal C differs depending on the value of the 2-bit data of the transmission data Data. Reference symbol M represents a frequency-divided signal obtained by dividing the clock Clock by two.

  That is, when the 2-bit data is (0, 0), the selection signal f is “H”, the second phase control path SLf is selected, the delay is the reference (0), and the output signal C is the falling edge of the clock. Change at the edge.

  In practice, the output signal C changes after a lapse of time longer than the delay of the second phase control path SLf from the falling edge of the clock. In FIG. 11, for ease of understanding, the reference (0) At this time, the output signal C is drawn to change at the falling edge of Clock.

  When the 2-bit data is (1, 0), the selection signal g is “H”, the third phase control path SLg is selected, and the output signal C is delayed by π / 2 compared to the reference (+ π / 2). Change in phase. Further, when the 2-bit data is (1, 1), the selection signal h is “H”, the fourth phase control path SLh is selected, and the output signal C has a phase that is delayed by π (+ π) from the reference. Change. When the 2-bit data is (0, 1), the selection signal e is “H”, the first phase control path SLe is selected, and the output signal C is advanced by π / 2 compared to the reference (−π / 2) phase.

  FIG. 12 is a timing chart for explaining the operation of the impulse transmitter according to the first embodiment. Here, FIG. 12 shows a communication clock Clock, transmission data Data, selection signals e, f, g, h, an output signal C of the T-FF 902, an output signal D of the pulse generation filter 506, and an impulse signal (millimeter wave pulse). ).

  As shown in FIG. 12, for example, when the transmission data Data changes to “001011010100...”, Any of the selection signals e, f, g, and h is selected based on the value of 2-bit data (2-bit data pattern). One becomes “H” and the other three become “L”. By controlling the delay amount (phase) of the variable delay unit 920 based on the selection signals e, f, g, and h, the transition timing of the output signal C is adjusted, and the changing edge of the signal C is shifted.

  Then, at the changing edge of the shifted signal C, a positive or negative impulse is generated according to the changing direction of C. That is, a millimeter wave pulse as shown in FIG. 12 is generated, amplified by the transmission amplifier 104 described with reference to FIG. 1, for example, and the transmission signal is wirelessly transmitted via the transmission antenna 105.

  FIG. 13 is a block diagram showing an example of an impulse receiver that receives a signal from the impulse transmitter of the first embodiment, and multiplexes by changing the phase output from the impulse transmitter of the first embodiment. 1 shows an example of a receiver that receives a bipolar impulse signal.

  Here, as described with reference to FIG. 1, the impulse receiver includes a reception antenna 121, a reception amplifier 122, a detector 123, a limit amplifier 124, and a baseband signal regenerator 125. The reception amplifier 122 is realized by, for example, a low noise amplifier.

  The detector 123 includes a bipolar short pulse generator 805, a bandpass filter 802, a first mixer 803A, a second mixer 803B, and a π / 2 phase shifter 804. The bipolar short pulse generator 805 generates a short pulse whose polarity changes every half cycle of the frequency signal (divided by 2 signal) obtained by dividing the communication clock Clock by the multiplicity (here, “2”).

  That is, the bipolar short pulse generator 805 is, for example, a local oscillation signal having a center frequency (for example, 83.5 GHz) in the pass band of the bandpass filter 103 of the impulse transmitter, and a bipolar having a positive polarity and a negative polarity alternately changing. Generate short pulses.

  As described above, the impulse receiver shown in FIG. 13 uses the bipolar short pulse generator 805 instead of the unipolar short pulse generator 801 in the detector 123 in the impulse receiver described with reference to FIG. The point is different.

  The bandpass filter 802 has the same pass characteristics as the bandpass filter 103 of the transmitter, receives the output signal of the bipolar short pulse generator 805, is an oscillation signal having the same frequency as the vibration signal, and has a short envelope. A pulse signal corresponding to the pulse signal is generated.

  The first mixer 803A performs detection by mixing the output signal of the reception amplifier 122 with the pulse signal output from the bandpass filter 802. The second mixer 803B shifts the phase of the pulse signal output from the bandpass filter 802 by π / 2 by the π / 2 phase shifter 804 to the output signal of the reception amplifier 122, and mixes the phase-shifted signal. And detect. This provides an intermediate frequency (IF) signal.

  The limit amplifier 124 includes a first amplifier 124A that amplifies the output of the first mixer 803A, and a second amplifier 124B that amplifies the output of the second mixer 803B. Here, the local oscillation signals mixed by the first mixer 803A and the second mixer 803B are out of phase by π / 2 (for example, 3 ps), and the IF signal (Q signal) is output from the first amplifier 124A. An IF signal (I signal) is output from the second amplifier 124B.

  Here, since the bipolar short pulse generator 805 generates a bipolar short pulse in which the positive polarity and the negative polarity are alternately changed, the output of the bandpass filter 802 is also alternately changed in the positive polarity and the negative polarity.

  Also, as described with reference to FIGS. 8 to 12, the impulse signal output from the impulse transmitter of the first embodiment is input to the first mixer 803A and the second mixer 803B via the reception amplifier 122. The signal is detected by the output of the bandpass filter 802.

  That is, the first mixer 803A and the second mixer 803B are bipolar signals whose polarity changes alternately (the output signal of the bandpass filter 802 and the signal shifted by π / 2 from the output signal, and the polarity changes alternately). Signal).

  As a result, the signal by phase modulation by the output signal (C) of any of the four phase control paths SLe to SLh selected by the four selection signals e to h is detected without error, and the IF signals (Q and I Signal).

  The baseband signal regenerator 125 includes an analog-to-digital converter (ADC) 851, a phase detector 852, and a data regenerator 853. The ADC 851 converts the IF signal (Q) and the IF signal (I) into digital data.

  The phase detector 852 detects the phase of the received impulse signal from the digital data of the IF signal (Q) and the IF signal (I). The data reproducing unit 853 reproduces data from the detected phase and the received clock phase.

  FIG. 14 is a timing chart showing an example of signals in each part of the impulse receiver shown in FIG. As shown in FIG. 14, 2-bit data is received for each period of the communication clock Clock, and the phase of the divided clock (0 to π or π to 2π (0)) obtained by dividing the Clock by two and The phase of the impulse signal (millimeter wave pulse) differs according to the 2-bit data.

  When the local (LO) signal (Q) and the local (LO) signal (Q) having different π / 2 phases are mixed with each other, an IF signal (Q) and an IF signal (I) are obtained. The received data can be determined according to the positive / negative combination of the IF signal (Q) and the IF signal (I).

  Thus, the impulse signal output from the impulse transmitter as shown in FIG. 8 can be correctly reproduced by the impulse receiver in which the bipolar short pulse generator 805 is applied to the detector 123 as shown in FIG. .

  Thereby, for example, it is possible to further improve the frequency utilization efficiency while maintaining the line spectrum suppression which is the merit of the bipolar impulse signal, and further, the T-FF902 (variable delay unit 920 with position modulation function of the transmitter). ) Can be simplified.

  FIG. 15 is a diagram showing an example of a short pulse generator in the second embodiment of the impulse transmitter, which controls the amplitude of the pulse to achieve multi-value. That is, the second embodiment does not control the appearance position (phase) of the impulse signal of the first embodiment described above, but improves the amplitude (intensity) of the impulse signal in order to improve the frequency utilization efficiency in the impulse radio communication system. ) Is controlled to achieve multi-value.

  As is apparent from the comparison between FIG. 15 and FIG. 8A, in the second embodiment, the selector 901, together with the selection signals e, f, g, and h, has an amplitude for controlling the amplitude of the pulse. A control signal SS is generated and output to the amplitude control circuit 300 provided in the edge shaping circuit 505. Here, the edge shaping circuit 505 includes, for example, an even number of inverters connected in series.

  FIG. 16 is a diagram for explaining an example of an amplitude control circuit applied to the impulse transmitter shown in FIG. 15, and two amplitude levels are obtained by controlling the back gate of the inverter included in the edge shaping circuit 505. An amplitude control circuit 300 is shown. Here, FIG. 16A shows a circuit configuration of the amplitude control circuit 300, and FIG. 16B shows an example of an operation waveform by the amplitude control circuit 300.

  As shown in FIG. 16 (a), the amplitude control circuit 300 includes a digital / analog converter (DAC) 302. For example, the amplitude control circuit 300 is different by controlling the back gate of one inverter 301 included in the edge shaping circuit 505. Two amplitude levels are obtained.

  The amplitude control circuit 300 receives the amplitude control signal SS from the selector 901, generates a rising transition control signal (control voltage) Trc and a falling transition control signal Trf, and controls the inverter (CMOS inverter) 301.

  That is, the back gate voltage of the pMOS transistor 311 in the inverter 301 is controlled by the rising transition control signal Trc, and the back gate voltage of the nMOS transistor 312 is controlled by the falling transition control signal Trf.

  Specifically, as shown in FIG. 16B, when SS is “0 (low level)”, Trc = 1.2V and Trf = 0.2V are set, whereby the output of the edge shaping circuit 505 is obtained. The transition of the signal C0 becomes steep (transition time is shortened). As a result, the amplitude (intensity) of the output signal D of the pulse generation filter (bandpass filter) 506 increases.

  On the other hand, when SS is “1 (high level)”, Trc = 1V and Trf = 0V are set, whereby the transition of the output signal C0 of the edge shaping circuit 505 becomes gentle (the transition time becomes long). As a result, the amplitude of the output signal D of the pulse generation filter 506 is reduced.

  Thereby, the amplitude of the impulse output from the transmitter can be controlled by two levels of magnitude. Here, as the inverter 301 of the amplitude control circuit 300, it is preferable to apply an inverter other than the final stage in consideration of the stability of the circuit.

  FIG. 17 is a diagram for explaining another example of the amplitude control circuit applied to the impulse transmitter shown in FIG. 15, and controls the power supply voltage Vdc (Vdd) of the inverter 301 included in the edge shaping circuit 505. An amplitude control circuit 300 ′ that obtains two amplitude levels is shown. Here, FIG. 17A shows a circuit configuration of the amplitude control circuit 300 ′, and FIG. 17B shows an example of an operation waveform by the amplitude control circuit 300 ′.

  The amplitude control circuit 300 described with reference to FIG. 16 fixes the power supply voltage Vdd (for example, 1.2 V) and controls the back gate voltage of the inverter 301 to obtain pulses having different amplitudes. The example amplitude control circuit 300 ′ directly controls the power supply voltage Vdd (Vdc).

  Since the amplitude control circuit 300 ′ shown in FIG. 17 transmits information by a pair of positive and negative pulses, for example, when controlling the amplitude of the pulse at two large and small levels, multiplexing by amplitude control is performed. The effect of the conversion is 0.5 bits.

  The amplitude control circuit 300 ′ includes an inverter 301, a DAC 302, and a latch 303. The latch 303 does not change the power supply voltage Vdc (Vdd) when the output C of the T-FF 902 is “1”, and outputs a signal K that changes the power supply voltage Vdc when the output C is “0”.

  That is, the amplitude control circuit 300 ′ controls the power supply voltage Vdc of the inverter 301 based on a positive / negative pair of bipolar impulse signals. The power supply voltage (Vss) on the low potential side is fixed at 0V, for example.

  Specifically, as shown in FIG. 17B, for example, when the output signal K of the latch 303 is “0”, Vdc = 1.2 V, and thus the output signal C0 of the edge shaping circuit 505 is changed. The amplitude increases, and the amplitude (intensity) of the output signal D of the pulse generation filter 506 also increases.

  On the other hand, when K is “1”, Vdc = 0.6 V, whereby the amplitude of the output signal C0 of the edge shaping circuit 505 is reduced and the amplitude of the output signal D of the pulse generation filter 506 is also reduced.

  Thereby, the amplitude of the impulse output from the transmitter can be controlled by two levels of large and small with a pair of positive and negative pulses. As the inverter 301 of the amplitude control circuit 300 ′, it is preferable to apply an inverter other than the final stage as in the amplitude control circuit 300.

  Thus, according to the second embodiment, multi-value can be achieved by controlling the amplitude of the impulse (bipolar impulse) output from the transmitter. Here, it is needless to say that the pulse position (phase) modulation according to the first embodiment described above can be combined with the pulse amplitude modulation according to the second embodiment.

  The second embodiment can be applied not only to the impulse transmitter (short pulse generator) shown in FIG. 8, for example, but also to the impulse transmitter shown in FIG. Further, the multi-leveling based on the amplitude of the impulse is not limited to the two levels, large and small, due to the frequency used, environmental noise, and the like, and further multi-leveling can be achieved.

  FIG. 18 is a diagram for explaining a modification of the impulse transmitter of the second embodiment. In the impulse transmitter of the first embodiment shown in FIG. 8, the amplitude control circuit 300 (300 ′) generates short pulses. This is adaptable to the T-FF 902 (variable delay unit 920) of the device 102.

  As is clear from the comparison between FIG. 18 and FIG. 8B described above, in the variable delay unit 920 ′ of this modification, one buffer that gives the same delay to each of the phase control paths SLe to SLh is provided. Have been added.

  That is, the first phase control path SLe includes one buffer (unit buffer) 928, the delay due to this buffer corresponds to a phase of −π / 2, and the second phase control path SLf includes two buffer strings. 923 ′, and the delay due to this buffer string corresponds to the reference (0).

  Further, the third phase control path SLg includes three buffer columns 925 ′, the delay due to this buffer column corresponds to a phase of + π / 2, and the fourth phase control path SLh includes four buffer columns 927 ′. The delay due to this buffer string corresponds to the phase of the reference + π.

  In this way, even if buffers that give the same delay are added to the respective phase control paths SLe to SLh, the relative phase relationship does not change. In FIG. 18, one buffer can be formed, for example, by connecting an even number of inverters in series.

  In the second embodiment described with reference to FIGS. 15 to 17, the example in which the inverter in the edge shaping circuit 505 is applied as the inverter 301 of the amplitude control circuit 300 (300 ′), but each phase control path SLe is shown. An inverter at ~ SLh may be applied.

  In this case, one inverter in the buffer 928 or the buffer train 923 ′, 925 ′, 927 ′ of each phase control path SLe to SLh is used as the inverter 301 of the amplitude control circuit 300 (300 ′).

  In this case, the inverter used as the inverter 301 is preferably an inverter other than the final stage in each of the phase control paths SLe to SLh in consideration of circuit stability.

  Although the embodiment has been described above, all examples and conditions described herein are described for the purpose of helping understanding of the concept of the invention applied to the invention and the technology. It is not intended to limit the scope of the invention. Nor does such a description of the specification indicate an advantage or disadvantage of the invention. Although embodiments of the invention have been described in detail, it should be understood that various changes, substitutions and modifications can be made without departing from the spirit and scope of the invention.

Regarding the embodiment including the above examples, the following supplementary notes are further disclosed.
(Appendix 1)
An impulse transmitter for transmitting a multiplexed bipolar impulse signal with changing phase,
A baseband signal generator that generates a data signal in units of time slots of a communication clock;
A short pulse generator for generating a bipolar short pulse with the polarity reversed based on the data signal;
A bandpass filter that receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal;
The short pulse generator is
A trigger flip-flop with a position modulation function including a number of phase control paths based on the multiplicity of multiplexing, changing the phase of the bipolar short pulse by giving different delays;
An impulse transmitter characterized by that.

(Appendix 2)
The number of the phase control paths is 2 ^N where N is the multiplicity.
The impulse transmitter as set forth in Appendix 1, wherein

(Appendix 3)
The multiplicity is 2,
The phase control paths give phases “−π / 2”, “0”, “+ π / 2” and “+ π”, respectively.
The impulse transmitter according to supplementary note 2, wherein

(Appendix 4)
The short pulse generator further comprises:
Including a selector for generating a selection signal corresponding to the multiplicity from transmission data, and selecting any one phase control path in the phase control path;
The impulse transmitter according to any one of Supplementary Note 1 to Supplementary Note 3, wherein:

(Appendix 5)
The short pulse generator further comprises:
An edge shaping circuit that shapes the output of the trigger flip-flop with the position modulation function;
The impulse transmitter according to any one of Supplementary Note 1 to Supplementary Note 4, wherein:

(Appendix 6)
further,
A transmission amplifier that amplifies the bipolar impulse signal that has passed through the bandpass filter and outputs the amplified signal from an antenna;
The impulse transmitter according to any one of Supplementary Note 1 to Supplementary Note 5, wherein:

(Appendix 7)
The bipolar impulse signal from the impulse transmitter is received by an impulse receiver having a bipolar short pulse generator that generates a reception short pulse signal whose polarity is inverted as a short pulse generator for reception, and data is reproduced. Done,
The impulse transmitter according to any one of Supplementary Note 1 to Supplementary Note 6, wherein:

(Appendix 8)
An impulse receiver that receives a bipolar impulse signal from the impulse transmitter according to any one of appendix 1 to appendix 6 and reproduces data;
A receiving amplifier for amplifying the received signal of the receiving antenna;
A detector for detecting the output of the receiving amplifier,
The detector is
A bipolar short pulse generator for generating a received short pulse signal whose polarity is inverted;
A reception bandpass filter that passes the output of the short pulse generator and generates a local signal;
A mixer for detecting the output of the receiving amplifier in response to the local signal,
An impulse receiver.

(Appendix 9)
The impulse transmitter according to any one of supplementary notes 1 to 6,
An impulse receiver according to appendix 8, and
An impulse radio communication system.

(Appendix 10)
An impulse transmitter that transmits a bipolar impulse signal composed of vibration signals of opposite phase according to polarity,
A baseband signal generator that generates a data signal in units of time slots of a communication clock;
A short pulse generator for generating a bipolar short pulse with the polarity reversed based on the data signal;
A bandpass filter that receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal;
The short pulse generator is
An amplitude control circuit that multiplexes by changing the amplitude of the bipolar impulse signal;
An impulse transmitter characterized by that.

(Appendix 11)
The amplitude control circuit controls the back gate voltage of the inverter to change the amplitude of the bipolar impulse signal.
The impulse transmitter according to supplementary note 10, characterized by that.

(Appendix 12)
The amplitude control circuit controls the power supply voltage of the inverter based on a positive / negative pair of bipolar impulse signals, and changes the amplitude of the bipolar impulse signals.
The impulse transmitter according to supplementary note 10, characterized by that.

(Appendix 13)
The short pulse generator further comprises:
It has an edge shaping circuit that shapes and outputs the waveform,
The inverter controlled by the amplitude control circuit is an inverter that forms the edge shaping circuit.
The impulse transmitter according to any one of Supplementary Note 10 to Supplementary Note 12, which is characterized in that.

(Appendix 14)
The inverter controlled by the amplitude control circuit is
An inverter that forms an edge shaping circuit that shapes the output of the trigger flip-flop with position modulation function according to appendix 5, or an inverter that forms a buffer in each phase control path of the trigger flip-flop with position modulation function ,
The impulse transmitter according to any one of Supplementary Note 10 to Supplementary Note 13, which is characterized in that.

(Appendix 15)
The inverter controlled by the amplitude control circuit is
It is an inverter other than the final stage.
The impulse transmitter according to appendix 14, wherein

DESCRIPTION OF SYMBOLS 101 Baseband signal generation part 102 Short pulse generator 103 Band pass filter 104 Transmission amplifier 105 Transmission antenna 121 Reception antenna 122 Reception amplifier 123 Detector 124 Limit amplifier 125 Baseband signal regenerator 300,300 'Amplitude control circuit 505 Edge shaping ( (Shaping) circuit 506 Pulse generation filter (band pass filter)
507 Pulse amplifier (transmission amplifier)
701, 901 Selector 702, 902 Trigger flip-flop with position modulation function (T-FF: short pulse generator)
720, 920, 920 'Variable delay unit 801 Unipolar short pulse generator 802 Band pass filter 803A Mixer (first mixer)
803B mixer (second mixer)
804 π / 2 phase shifter 805 bipolar short pulse generator

Claims (10)

An impulse transmitter for transmitting a multiplexed bipolar impulse signal with changing phase,
A baseband signal generator that generates a data signal in units of time slots of a communication clock;
A short pulse generator for generating a bipolar short pulse with the polarity reversed based on the data signal;
A bandpass filter that receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal;
The short pulse generator is
A trigger flip-flop with a position modulation function including a number of phase control paths based on the multiplicity of multiplexing, changing the phase of the bipolar short pulse by giving different delays;
An impulse transmitter characterized by that. The number of the phase control paths is 2 ^N where N is the multiplicity.
The impulse transmitter according to claim 1. The short pulse generator further comprises:
An edge shaping circuit that shapes the output of the trigger flip-flop with the position modulation function;
The impulse transmitter according to claim 1 or 2, characterized by the above. The bipolar impulse signal from the impulse transmitter is received by an impulse receiver having a bipolar short pulse generator that generates a reception short pulse signal whose polarity is inverted as a short pulse generator for reception, and data is reproduced. Done,
The impulse transmitter according to any one of claims 1 to 3, wherein the impulse transmitter is provided. An impulse receiver for reproducing data by receiving a bipolar impulse signal from the impulse transmitter according to any one of claims 1 to 3,
A receiving amplifier for amplifying the received signal of the receiving antenna;
A detector for detecting the output of the receiving amplifier,
The detector is
A bipolar short pulse generator for generating a received short pulse signal whose polarity is inverted;
A reception bandpass filter that passes the output of the short pulse generator and generates a local signal;
A mixer for detecting the output of the receiving amplifier in response to the local signal,
An impulse receiver. The impulse transmitter according to any one of claims 1 to 3,
An impulse receiver according to claim 5,
An impulse radio communication system. An impulse transmitter that transmits a bipolar impulse signal composed of vibration signals of opposite phase according to polarity,
A baseband signal generator that generates a data signal in units of time slots of a communication clock;
A short pulse generator for generating a bipolar short pulse with the polarity reversed based on the data signal;
A bandpass filter that receives the bipolar short pulse and passes only a predetermined frequency bandwidth to generate the bipolar impulse signal;
The short pulse generator is
An amplitude control circuit that multiplexes by changing the amplitude of the bipolar impulse signal;
An impulse transmitter characterized by that. The amplitude control circuit controls the back gate voltage of the inverter to change the amplitude of the bipolar impulse signal.
The impulse transmitter according to claim 7. The amplitude control circuit controls the power supply voltage of the inverter based on a positive / negative pair of bipolar impulse signals, and changes the amplitude of the bipolar impulse signals.
The impulse transmitter according to claim 7. The inverter controlled by the amplitude control circuit is
An inverter that forms an edge shaping circuit that shapes the output of the trigger flip-flop with position modulation function according to claim 3, or an inverter that forms a buffer in each phase control path of the trigger flip-flop with position modulation function is there,
The impulse transmitter according to any one of claims 7 to 9, wherein the impulse transmitter is provided.

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