WO2011004849A1 - ダイバーシチ受信装置 - Google Patents
ダイバーシチ受信装置 Download PDFInfo
- Publication number
- WO2011004849A1 WO2011004849A1 PCT/JP2010/061558 JP2010061558W WO2011004849A1 WO 2011004849 A1 WO2011004849 A1 WO 2011004849A1 JP 2010061558 W JP2010061558 W JP 2010061558W WO 2011004849 A1 WO2011004849 A1 WO 2011004849A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- antenna
- phase
- antennas
- measured
- correlation coefficient
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
- H04B7/0842—Weighted combining
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0802—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using antenna selection
- H04B7/0825—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using antenna selection with main and with auxiliary or diversity antennas
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
- H04B7/084—Equal gain combining, only phase adjustments
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0868—Hybrid systems, i.e. switching and combining
- H04B7/0874—Hybrid systems, i.e. switching and combining using subgroups of receive antennas
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0891—Space-time diversity
- H04B7/0894—Space-time diversity using different delays between antennas
Definitions
- the present invention relates to a diversity receiving apparatus, and more particularly to a diversity receiving apparatus suitable for a terrestrial digital broadcast tuner for in-vehicle use.
- a terrestrial digital high-definition broadcasting tuner for in-vehicle use, when normal 12-segment broadcasting (hereinafter abbreviated as 12-segment broadcasting) cannot be received due to deterioration of the reception state, it is automatically modulated in a fading-resistant manner. Switching to reception of 1 segment broadcasting (hereinafter abbreviated as 1 segment broadcasting).
- 1 segment broadcasting In the terrestrial integrated digital broadcasting service (ISDB-T) system, which is a Japanese broadcasting standard based on the provisions of Article 38 of the Radio Law, the UHF band is used as the frequency band, and the 1 channel 6 MHz band is 12 segments for fixed reception, It can be transmitted in one segment for mobile reception.
- ISDB-T terrestrial integrated digital broadcasting service
- orthogonal frequency division multiplexing In the ISDB-T system, orthogonal frequency division multiplexing (OFDM) is used as a multiplexing system, and 16-value quadrature amplitude modulation (16QAM), 64-value quadrature amplitude modulation 64QAM, 4-phase modulation (QPSK), Differential quadrature phase modulation (DQPSK) can be used.
- 16QAM 16-value quadrature amplitude modulation
- 64QAM 64-value quadrature amplitude modulation
- QPSK 4-phase modulation
- DQPSK Differential quadrature phase modulation
- modes 1 to 3 having different OFDM carrier intervals as transmission parameters.
- a 12-segment broadcast reception tuner uses digital beamforming (DBF) to ensure a high carrier-to-noise power ratio (CNR).
- DBF digital beamforming
- CNR carrier-to-noise power ratio
- Phase synthesis diversity is used.
- the number of receivers required is the same as the number of antennas. Therefore, terrestrial digital broadcast tuners for automobiles are commercially available at a price three to four times that of home terrestrial digital broadcast tuners.
- a DBF is mounted on a mobile device such as a notebook PC, there is a problem that power consumption increases and viewing time is shortened.
- Non-Patent Document 1 As a variable directivity antenna that requires only one receiving system, a phased array (see Patent Document 1, Non-Patent Document 1), a load reflected current control type adaptive antenna (see Non-Patent Document 2), an electronic scanning waveguide (ESPAR) antenna (see Non-Patent Document 3). Since these antennas cannot directly observe the received signal of each element, it is necessary to use a blind algorithm for the weight search. In general, the blind algorithm has a long convergence time, and is often difficult to apply at high speed. For the weight search, it is necessary to perform a trial operation of a phase shifter in the phased array and a variable reactor in the ESPAR antenna. Since this corresponds to a channel change in the reception branch, when applied to reception by the ISDB-T method, symbol synchronization is lost and BER characteristics are deteriorated.
- the present invention has a simple structure, improves the bit error rate (BER) without using a blind algorithm, does not require carrier synchronization, and can achieve a diversity effect even if sampling is performed at a speed lower than the sampling theorem.
- An object is to provide an apparatus.
- a first aspect of the present invention includes (a) a first antenna that serves as a reference antenna, (b) a second antenna that serves as an antenna to be measured, and (c) first and A power combiner that combines the OFDM signals received by each of the second antennas; (d) a terrestrial digital broadcast tuner connected to the output side of the power combiner; and (e) a midway in the effective symbol period of the OFDM signal.
- a switch for switching between the branch output of the first antenna and the branch output of the second antenna for each symbol period (f) a receiver connected to the output side of the switch and demodulating the OFDM signal, (g ) A phase shifter connected to the output side of the second antenna and phase-shifted for the OFDM signal received by the second antenna, and then output to the power combiner; and (h) a demodulated signal is input for each symbol interval.
- the complex correlation coefficient between the guard interval of the first antenna and the copy source interval of the second antenna is calculated, the rotation angle in the complex plane is obtained from the complex correlation coefficient, and the phase shifter shifts the phase by the rotation angle.
- a diversity reception device including an arithmetic processing circuit that outputs a signal.
- a reference antenna (b) a plurality of antennas to be measured, and (c) power combining that combines the OFDM signals received by each of the reference antenna and the plurality of antennas to be measured.
- a digital terrestrial broadcast tuner connected to the output side of the power combiner, and (e) a branch output of a reference antenna and a plurality of measured signals for each symbol section in the middle of an effective symbol section of the OFDM signal.
- a switch for switching one of the branch outputs of the antenna (f) a receiver connected to the output side of the switch and demodulating the OFDM signal; and (g) connected to each of the output sides of the plurality of antennas under measurement.
- the gist of the present invention is a diversity receiver including an arithmetic processing circuit that performs a process of outputting a signal to be phase-shifted by one rotation angle to any of the phase shifters of the antenna under measurement. .
- a bit error rate (BER) is improved without using a blind algorithm with a simple structure, carrier synchronization is not required, and a diversity effect can be expected even if sampling is performed at a speed lower than the sampling theorem. It is possible to provide a diversity receiver.
- FIG. 1A It is a typical block diagram explaining the outline of the diversity receiver which concerns on the 1st Embodiment of this invention.
- the first antenna and the second antenna are switched for each symbol interval, and the first antenna guard interval and the second antenna copy are switched.
- FIG. 5 shows BER-CNR characteristics for explaining the influence of phase correction delay in the diversity receiver according to the first embodiment.
- the absolute value of the complex correlation coefficient is not multiplied by ⁇ .
- the diversity receiving apparatus in which the reception band is limited to 2 MHz, sampled at 500 ksps, and the phase of the copy source section T is advanced by ⁇ / 3 and the amplitude is 0.3 times. It is a figure which shows the amplitude and phase of a complex correlation coefficient in the state where noise was added (the absolute value of a complex correlation coefficient is not multiplied by ⁇ ). It is a figure which shows the time change of the phase difference between branches when a Doppler frequency is 0 Hz in the diversity receiver which concerns on 1st Embodiment.
- FIG. 12 is a diagram illustrating a demodulated signal of a 64QAM I channel when the Doppler frequency is 0 Hz in the diversity receiver according to the first embodiment.
- FIG. 12A illustrates a case where there is no delayed wave, and FIG. When there is a delayed wave.
- FIG. 12A illustrates a case where there is no delayed wave
- FIG. 12A illustrates a case where there is no delayed wave
- FIG. When there is a delayed wave It is a figure which shows the time change of the absolute value of a correlation coefficient in the diversity receiver which concerns on 1st Embodiment when there exists a delay wave.
- the first antenna and the fourth antenna are switched to the first symbol interval, the complex correlation coefficient between the first antenna guard interval and the second antenna copy source interval, the first antenna guard interval and the second antenna interval 3 is a time chart illustrating a mode of sequentially calculating a complex correlation coefficient with a copy source section of the third antenna and a complex correlation coefficient between a guard section of the first antenna and a copy source section of the fourth antenna.
- 10 is a time chart illustrating a mode in which phase correction of three antennas to be measured is performed within one symbol section in a 4-branch diversity receiver according to a fourth embodiment.
- the diversity receiver according to the first embodiment of the present invention includes a first antenna A1 serving as a reference antenna, a second antenna A2 serving as a measured antenna, and a first antenna.
- a power combiner 14 that combines the power of the OFDM signals received by each of the A1 and the second antenna A2, a terrestrial digital broadcast tuner 15 connected to the output side of the power combiner 14, and an effective symbol section of the OFDM signal ,
- a switch S that switches between the branch output of the first antenna A1 and the branch output of the second antenna A2 for each symbol period, and a receiver 21 that is connected to the output side of the switch S and demodulates the OFDM signal, It is connected to the output side of the second antenna A2, and after the OFDM signal received by the second antenna A2 is phase-shifted, it is output to the power combiner 14.
- a phase shifter 13 and an arithmetic processing circuit 22 that inputs a demodulated signal from the receiver 21 and outputs a signal that causes the phase shifter 13 to shift the phase by the rotation angle.
- the first directional coupler 11 is connected to the output side of the first antenna A1, a part of the output of the first antenna A1 is branched to the switch S side, and the first directional coupler 11 is connected to the output side of the second antenna A2.
- Two directional couplers 12 are connected, and a part of the output of the second antenna A2 is branched to the switch S side.
- a part of the output of the first antenna A1 is input to the power combiner 14 via the first directional coupler 11, and a part of the output of the second antenna A2 is input to the second directional coupler 12. , And input via the phase shifter 13.
- a microprocessor such as a digital signal processor (DSP) can be used.
- the signal of the receiver 21 is AD converted and input to the arithmetic processing circuit 22, and the output signal of the arithmetic processing circuit 22 is DA converted.
- DSP digital signal processor
- Each structure of the first antenna A1 and the second antenna A2 is, for example, an external antenna such as a monopole antenna or a helical antenna, a so-called inverted F antenna of a PIFA (planer inverted-F antenna) system, a bent mono A built-in antenna such as a pole type antenna or a planar substrate antenna using a printed circuit board in which a planar balun is configured with a wiring pattern can be adopted.
- the first antenna A1 and the second antenna A2 are cylindrical conductors.
- the antenna is not limited to a bar, and includes various antennas including a planar antenna (such as a patch antenna).
- the terrestrial digital broadcast tuner 15 selects the OFDM signal transmitted from the power combiner 14 and down-converts the selected signal to a predetermined band, as well as an A / D converter, a quadrature detection circuit, a synchronization Known circuit configurations such as a circuit, a fast Fourier transform (FFT) circuit, an equalization circuit, a deinterleave circuit, and a correction circuit are provided.
- FFT fast Fourier transform
- the first antenna A1 and the second antenna A2 have OFDM signals in which a guard interval GI is provided in each symbol interval S j , S j + 1 ,. Is entered.
- Each guard interval GI cyclically copies the waveform of the copy source interval T in the latter half of the effective symbol interval of each symbol interval S j , S j + 1 ,... As a dummy signal.
- the arithmetic processing circuit (DSP) 22 shown in FIG. 1A switches the first antenna A1 and the second antenna A2 for each symbol period S j , S j + 1 ,... Of the OFDM signal shown in FIG.
- the complex correlation coefficient ⁇ between the guard section GI of the antenna A1 and the copy source section T of the second antenna A2 is calculated, and the rotation angle in the complex plane is obtained from the complex correlation coefficient to receive the second antenna A2. Correct the phase of the signal. For this reason, as shown in FIG. 2, the arithmetic processing circuit (DSP) 22 generates an antenna switching unit that generates a signal for switching to one of the first antenna A1 and the second antenna A2 and transmits the signal to the switch S.
- Complex correlation coefficient calculation means 223 for calculating the relation number ⁇ , rotation angle calculation means 224 for obtaining a rotation angle on the complex plane from the complex correlation coefficient calculated by the complex correlation coefficient calculation means 223, and rotation angle calculation means 224
- the phase shift means 225 generates a signal for shifting the phase of the received signal of the second antenna A2 in the opposite direction by the rotation angle calculated by Provided.
- step S101 the antenna switching means 221 of the arithmetic processing circuit (DSP) 22 transmits a signal DO to the switch S, and switches to one of the first antenna A1 and the second antenna A2. .
- DSP arithmetic processing circuit
- step S101 the symbol synchronization means 222 establishes symbol synchronization by sliding correlation or the like.
- step S103 the antenna switching means 221 transmits a signal DO to the switch S, and as shown in FIG. 1B, near the center of each symbol section S j , S j + 1 ,.
- the branch is switched to one of the first antenna A1 and the second antenna A2.
- the receiver 21 includes signals A1 j , A1 j + 1 ,...
- step S103 the receiver 21, the signal A1 j, A1 j + 1 of the first antenna A1, ..., and signal A2 j, A2 j + 1 of the second antenna A2, demodulates the ... .
- the complex correlation coefficient calculating means 223 calculates the complex correlation coefficient ⁇ between the guard interval GI of the first antenna A1 and the copy source interval T of the second antenna A2 using equation (1):
- Equation (1) x i is a signal in the guard interval GI received by the first antenna A1, and y i is a signal in the copy source interval T of the guard interval GI received by the second antenna A2.
- the phase correction amount is calculated in the next symbol period S j + 1 , and then the next symbol period S j.
- the phase shifter is controlled at the head of +2 , and the phase is corrected. That is, at the head of each guard section GI in FIG. 1B, the timings ⁇ j-2 , ⁇ j ⁇ 1 , ⁇ j ,...
- the phase of the received signal of the second antenna A2 is sequentially corrected with a delay of one symbol period after data acquisition.
- the channel phase difference is directly obtained for each symbol period S j , S j + 1,.
- the diversity reception method according to the first embodiment if synchronization is established, only one complex correlation coefficient ⁇ is calculated, and the amount of calculation is small, so that it is possible to cope with high-speed fading.
- the diversity reception method according to the first embodiment can use an existing terrestrial digital broadcast tuner as it is.
- FIG. 4 shows the result of simulating the change of the reception channel voltage under Rayleigh fading with 2-branch diversity under the conditions shown in Table 1.
- the guard interval GI is 1/8 of the symbol length
- the modulation is 64QAM
- the Doppler frequency is 25 Hz.
- error correction is not performed to simplify the calculation.
- the vertical axis represents relative received voltage
- the horizontal axis represents time (seconds).
- the alternate long and short dash line is the first envelope
- the alternate long and two short dashes line is the received envelope in the second branch
- the dotted line is the ideal phase diversity (based on the channel estimation of each branch) when phase control is not performed. )
- the solid line is the reception envelope of the diversity receiver according to the first embodiment.
- the reception envelope of the diversity receiver according to the first embodiment is almost the same as the ideal phase shift diversity.
- the reflection of phase correction is delayed by at least one symbol even in the case of two-branch diversity.
- FIG. 5 shows the result of confirming the influence of delay by computer simulation.
- the simulation conditions in FIG. 5 are the same as those shown in Table 1, but in consideration of practical use, the transmission parameter symbol is set to mode 3 used in the current broadcasting system (prefecture area, fixed use). .
- FIG. 5 shows BER-CNR characteristics when the phase shift correction delay is 0 (no delay) and 1 or 2 symbols.
- FIG. 5 also shows the calculated BER-CNR characteristics when reception is performed with one antenna and selection diversity is performed with two antennas.
- FIG. 5 shows that the BER-CNR characteristics deteriorate as the phase correction delay increases from 1 symbol to 2 symbols. This is because if the delay occurs, the reflection of the phase cannot sufficiently follow the channel fluctuation due to fading.
- the BER is improved according to the diversity reception method according to the first embodiment.
- an improvement of about 10 dB is possible when the BER is around 10 ⁇ 2 .
- One feature of the system of the diversity receiver according to the first embodiment of the present invention is that it can be received using an existing television receiver as it is.
- the results of confirming by computer simulation that the correlation coefficient can be calculated without error even when the reception band of 5.5 MHz is limited to 2 MHz and the sampling rate of the AD converter is set to 500 ksps for low cost are shown in FIGS. Shown in In the computer simulation evaluations shown in FIGS. 6 to 9, no branch is switched and no fading is applied.
- FIG. 6 is a display of the I channel of a 64QAM signal in mode 3. No noise is added here.
- the vertical axis represents the reception level, and the horizontal axis represents the relative time. It can be seen that the received signal is smoothed by limiting the band to 2 MHz.
- the absolute value of the amplitude of the complex correlation coefficient when the band-limited signal is sampled at 500 ksps is indicated by a broken line, and the phase is indicated by a solid line.
- the absolute value of the complex correlation coefficient is multiplied by ⁇ for ease of viewing.
- the phase at the timing at which the absolute value of the complex correlation coefficient is the maximum is 0 because the same channel is received.
- the floor of the absolute value of the complex correlation coefficient rises and the phase change becomes small.
- FIG. 9 shows complex correlation coefficients when the phase of the copy source section T is ⁇ / 3 and the amplitude is 0.3.
- the absolute value of the complex correlation coefficient is not multiplied by ⁇ . It is indicated that the guard interval GI has a ⁇ / 3 phase delay from the copy source interval T.
- FIGS. 10 and 11 show the results of confirming by computer simulation whether or not complete carrier synchronization is necessary in the diversity receiver according to the first embodiment of the present invention.
- Figure 10 is a time variation of the phase difference between the branches when the 0Hz Doppler frequency f D
- FIG. 11 is a time variation of the phase difference between the branches when the Doppler frequency f D to 25 Hz.
- 10 (a) and 11 (a) are true phase differences
- FIGS. 10 (b) and 11 (b) are phase differences estimated by the system, which are demodulated by a local oscillator different from the carrier frequency by 1 kHz. As shown in FIG.
- the upper and lower phase curves are almost the same, and it can be seen that the diversity receiver according to the first embodiment can obtain the phase difference without taking perfect carrier synchronization.
- the feature of the ISDB-T system is that reception quality is not affected even if there is a delayed wave in the guard interval GI.
- the diversity receiver according to the first embodiment of the present invention obtains the phase difference using the reception envelope of each branch, it is considered that the phase calculation is affected.
- a random delay within the guard interval GI was generated, and a delayed wave having a logarithmic ratio (DU ratio) of the electric field strength between the target wave (direct wave) and the interference wave was 5 dB.
- the present inventors have measured the delay profile in the field at more than 50 locations in Tokyo, Kanagawa, and Hamamatsu, but no delayed wave exceeding the guard interval GI has been recognized so far. Further, delayed waves in the guard interval GI are often scattered, but the DU ratio is about 7 dB at the worst. The above condition seems to be the worst case.
- FIG. 12 is a display of a demodulated signal of an I channel (in-phase component) of 64QAM when the Doppler frequency f D is 0 Hz.
- FIG. 12A shows a case where there is no delayed wave, and FIG. There is a time.
- FIG. 12B it can be seen that the 64QAM demodulated signal changes greatly when a delay wave is applied.
- FIG. 13 shows the time change of the absolute value of the correlation coefficient when there is a delayed wave. It can be seen that the absolute value of the correlation coefficient decreases when there is a delayed wave.
- FIG. 14 shows the time change of the phase difference between the branches when the Doppler frequency f D is 0 Hz
- FIG. 15 shows the time change of the phase difference between the branches when the Doppler frequency f D is 25 Hz.
- 14 (a) and 15 (a) are true phase differences
- FIGS. 14 (b) and 15 (b) are the positions estimated by the diversity receiver according to the first embodiment when the delayed wave is superimposed. It is a phase difference. There is no significant effect on the phase even if the delay wave has a DU ratio of 5 dB, and it can be seen that the diversity receiver according to the first embodiment can perform robust operation in the field.
- the diversity receiver according to the first embodiment since it is sufficient to configure with one reception channel, low cost and low power consumption can be achieved. Furthermore, according to the diversity receiver according to the first embodiment, since iterative processing is not performed, it can be used in a high-speed fading environment. Furthermore, according to the diversity receiver according to the first embodiment, there is no need for carrier synchronization, operation is possible even at a sampling frequency lower than the Nyquist frequency, and operation in an environment with a delayed wave is also possible.
- the three-branch diversity receiver includes a first antenna A1 serving as a reference antenna and a second antenna A2 serving as a first antenna to be measured.
- a third antenna A3 serving as a second antenna to be measured;
- the terrestrial digital broadcast tuner 15 connected to the output side of the power combiner 14 and the branch output of the first antenna A1 and the branch output of the second antenna A2 for each symbol section in the middle of the effective symbol section of the OFDM signal
- a switch S that sequentially switches the branch output of the third antenna A3, and a receiver 21 that is connected to the output side of the switch S and demodulates the OFDM signal.
- the first phase shifter 13a connected to the output side of the second antenna A2 and phase-shifted in the OFDM signal received by the second antenna A2, and then output to the power combiner 14, and the third antenna A3 After the phase of the OFDM signal received by the third antenna A3 is shifted, the second phase shifter 13b output to the power combiner 14 and the demodulated signal from the receiver 21 are input. And an arithmetic processing circuit 22 that outputs a signal that causes the phase shifter 13a and the second phase shifter 13b to shift the phase by the rotation angle.
- a first directional coupler 11a is connected to the output side of the first antenna A1, a part of the output of the first antenna A1 is branched to the switch S side, and the first directional coupler 11a is connected to the output side of the second antenna A2.
- 2 directional coupler 11b is connected, a part of the output of the second antenna A2 is branched to the switch S side, and the third directional coupler 11c is connected to the output side of the third antenna A3, Part of the output of the third antenna A3 is branched to the switch S side.
- a part of the output of the first antenna A1 is input to the power combiner 14 via the first directional coupler 11, and a part of the output of the second antenna A2 is input to the second directional coupler 11b.
- the three-branch diversity receiver according to the second embodiment has one receiver 12, and the receiver 12 is connected to the first antenna A1, the second antenna A2, and the third antenna A3 via a switch S. Connected in a time-sharing manner.
- a microprocessor such as a DSP can be used as the arithmetic processing circuit 22 .
- the signal of the receiver 21 is AD-converted and input to the arithmetic processing circuit 22, and the output signal of the arithmetic processing circuit 22 is DA-converted to obtain the first signal.
- the signals are input to the phase shifter 13a and the second phase shifter 13b, respectively.
- various known antennas such as a monopole antenna, a helical antenna, a planar antenna (patch antenna, etc.) can be used as a monopole antenna, a helical antenna, a planar antenna (patch antenna, etc.) can be used.
- the first antenna A1, the second antenna A2, and the third antenna A3 are connected to the symbol intervals S j ⁇ 1 , S j , S j + 1 of the signal subjected to inverse discrete Fourier transform. , S j + 2 ,... Are input with an OFDM signal having a guard interval GI.
- a period obtained by subtracting the section length of the guard section GI from the section length of each symbol section S j ⁇ 1 , S j , S j + 1 , S j + 2 ,... Becomes an effective symbol section (observation window period).
- Each guard interval GI is cyclic as it is with the waveform of the copy source interval T in the latter half of the effective symbol interval of each symbol interval S j ⁇ 1 , S j , S j + 1 , S j + 2 ,.
- the first antenna A1 and the second antenna A2 are switched, and the complex correlation coefficient between the guard interval GI of the first antenna A1 and the copy source interval T of the second antenna A2.
- ⁇ 2 is calculated, and the first antenna A1 and the third antenna A3 are switched in the next symbol interval S j , and the complex between the guard interval GI of the first antenna A1 and the copy source interval T of the third antenna A3 is calculated.
- the correlation coefficient ⁇ 3 is calculated, and the first antenna A1 and the second antenna A2 are switched in the next symbol interval S j + 1 , and the first antenna A1 guard interval GI and the second antenna A2 are copied.
- the complex correlation coefficient ⁇ 2 with the original section T is calculated, the first antenna A1 and the third antenna A3 are switched in the next symbol section S j + 2 , and the guard sections GI and third of the first antenna A1 are switched. Copy of antenna A3
- the complex correlation coefficient ⁇ 3 with the original section T is calculated, and the rotation angle on the complex plane is sequentially obtained from the complex correlation coefficient, and the phase of the received signal of each of the second antenna A2 and the third antenna A3 Correct.
- the phase correction amount is calculated in the symbol section next to the symbol section from which data is acquired, and the phase shifter is controlled at the head of the subsequent symbol section to correct the phase. That is, timings ⁇ j-3 , ⁇ j-2 , ⁇ j-1 , ⁇ j , ⁇ j + 1 ,.
- the phase of the reception signal of each of the second antenna A2 and the third antenna A3 is delayed by one symbol period after each data acquisition, and the beginning of each symbol period Are corrected sequentially.
- the arithmetic processing circuit 22 in FIG. 16 is connected to any one of the first antenna A1, the second antenna A2, and the third antenna A3, as shown in FIG.
- An antenna switching unit 221 that generates a signal to be switched and transmits it to the switch S
- a symbol synchronization unit 222 that establishes symbol synchronization by sliding correlation or the like
- a guard interval GI of the first antenna A1 from the demodulated signal of the receiver 21 calculating the complex correlation coefficient [rho 3 as the source section T of the guard interval GI and the third antenna A3 of the complex correlation coefficients [rho 2 and the first antenna A1 to the copy source section T of the second antenna A2
- Complex correlation coefficient calculation means 223, rotation angle calculation means 224 for obtaining a rotation angle on the complex surface from the complex correlation coefficient calculated by the complex correlation coefficient calculation means 223, and rotation angle calculation means
- the first phase shifter 13a and the second phase shifter 13b are generated by shifting the phases of the reception signals of the second antenna A2 and the third antenna
- the phase is in the order of second antenna A 2 ⁇ third antenna A 3 ⁇ second antenna A 2 ⁇ antenna A 3. Since correction can be performed, even if there are three antennas, ie, the first antenna A1, the second antenna A2, and the third antenna A3, two receiver antennas are measured using one receiver 21. On the other hand, it is possible to correct the phase by calculating the phase difference in a time division manner.
- the 2-branch diversity receiving apparatus is described as an example, and in the second embodiment, the 3-branch diversity receiving apparatus is described as an example.
- the present invention is also applicable to a 4-branch diversity receiving apparatus.
- three antennas may be used.
- a 4-branch diversity receiver using four antennas one reference antenna and three antennas to be measured. There are many.
- the 4-branch diversity receiving apparatus includes a first antenna A1 serving as a reference antenna and a second antenna serving as a first antenna to be measured.
- A2 a third antenna A3 serving as a second antenna under measurement, a third antenna A4 serving as a third antenna under measurement, a first antenna A1, a second antenna A2, and a third antenna A3
- a power combiner 14 for combining the OFDM signals received by each of the fourth antennas A4, a terrestrial digital broadcast tuner 15 connected to the output side of the power combiner 14, and an effective symbol section of the OFDM signal.
- the branch output of the first antenna A1, the branch output of the second antenna A2, the branch output of the third antenna A3, and the fourth antenna A4 The switch S for sequentially switching the branch output, the receiver 21 that is connected to the output side of the switch S and demodulates the OFDM signal, and the OFDM that is connected to the output side of the second antenna A2 and received by the second antenna A2
- the first phase shifter 13a output to the power combiner 14 and the output side of the third antenna A3 are connected, and the OFDM signal received by the third antenna A3 is phase-shifted.
- a first directional coupler 11a is connected to the output side of the first antenna A1, a part of the output of the first antenna A1 is branched to the switch S side, and the first directional coupler 11a is connected to the output side of the second antenna A2.
- the 4-branch diversity receiver according to the third embodiment has one receiver 12, and the receiver 12 includes the first antenna A1, the second antenna A2, the third antenna A3, and the fourth antenna.
- A4 is connected to A4 through a switch S in a time division manner.
- a microprocessor such as a DSP can be used as the arithmetic processing circuit 22 .
- the signal of the receiver 21 is AD-converted and input to the arithmetic processing circuit 22, and the output signal of the arithmetic processing circuit 22 is DA-converted to obtain the first signal.
- the signals are input to the phase shifter 13a, the second phase shifter 13b, and the third phase shifter 13c, respectively.
- various known antennas may be used as the first antenna A1, the second antenna A2, the third antenna A3, and the fourth antenna A4. It can be used.
- the terrestrial digital broadcast tuner 15 can use a known circuit configuration, its detailed description is omitted.
- the first antenna A1, the second antenna A2, the third antenna A3, and the fourth antenna A4 are provided with symbol intervals S j-2 and S j of the signal subjected to inverse discrete Fourier transform.
- An OFDM signal provided with a guard interval GI is input to j ⁇ 1 , S j , S j + 1 , S j + 2 ,.
- Each guard interval GI is a dummy waveform of the copy source interval T in the latter half of the effective symbol interval of each symbol interval S j-2 , S j ⁇ 1 , S j , S j + 1 , S j + 2 ,. It is copied cyclically as a signal. Then, in the symbol interval S j-2 , the first antenna A1 and the second antenna A2 are switched, and the complex correlation coefficient between the guard interval GI of the first antenna A1 and the copy source interval T of the second antenna A2.
- ⁇ 2 is calculated, and the first antenna A1 and the third antenna A3 are switched in the next symbol interval S j ⁇ 1 , and the guard interval GI of the first antenna A1 and the copy source interval T of the third antenna A3 are copy of the complex correlation coefficients [rho 3 calculates, in the next symbol interval S j, the switching between the first antenna A1 to the fourth antenna A4, the guard interval GI and the fourth antenna A4 of the first antenna A1
- the complex correlation coefficient ⁇ 4 with the original section T is calculated, the first antenna A1 and the second antenna A2 are switched in the next symbol section S j + 1 , and the guard section GI and the second antenna of the first antenna A1 are switched.
- the complex correlation coefficient ⁇ 3 with the original section T is calculated, the first antenna A1 and the third antenna A3 are switched in the next symbol section S j + 2 , and the guard section GI and the first antenna section GI of the first antenna A1 are switched.
- the complex correlation coefficient ⁇ 3 with the copy source section T of the third antenna A3 is calculated, and the rotation angle on the complex plane is sequentially obtained from the complex correlation coefficient, and the second antenna A2, the third antenna A3, and the second antenna A3 are calculated.
- the phase of each received signal of the four antennas A4 is corrected.
- the phase correction amount is calculated in the symbol period next to the symbol period from which data is acquired, and the phase shifter is controlled at the head of the subsequent symbol period to correct the phase.
- phase correction timings ⁇ j-4 , ⁇ j-3 , ⁇ j-2 , ⁇ j-1 , ⁇ j , ⁇ j + 1 As indicated by the arrows, in the four-branch diversity receiver, the phase of each received signal of the second antenna A2, the third antenna A3, and the fourth antenna A4 is one after acquisition of the respective data. The correction is performed sequentially at the head of each symbol interval, delayed by the symbol interval.
- the arithmetic processing circuit 22 in FIG. 18 has the first antenna A1, the second antenna A2, the third antenna A3, and the fourth antenna A4, as shown in FIG. From the antenna switching means 221 for generating a signal to be switched to any one of the branches and transmitting to the switch S, the symbol synchronization means 222 for establishing symbol synchronization by sliding correlation or the like, and the demodulated signal of the receiver 21, the first antenna
- the complex correlation coefficient ⁇ 2 between the guard interval GI of A1 and the copy source interval T of the second antenna A2, and the complex phase relationship between the guard interval GI of the first antenna A1 and the copy source interval T of the third antenna A3 a complex correlation coefficient calculating means 223 for calculating the complex correlation coefficient [rho 4 and the number [rho 3 and the guard interval GI and the copy source section T of the fourth antenna A4 of the first antenna A1, double
- the rotation angle calculation means 224 for obtaining the rotation angle on the complex surface from the complex correlation coefficient calculated by the correlation coefficient calculation means 223,
- a signal for shifting the phase of the received signals of the antenna A3 and the fourth antenna A4 in the opposite direction is generated and transmitted to the first phase shifter 13a, the second phase shifter 13b, and the third phase shifter 13c, respectively.
- Phase shift means 225 is provided.
- each symbol section S j ⁇ 2 , S j ⁇ 1 , S j , S j + 1 , S j + 2 since the second antenna A2 ⁇ the third antenna A3 ⁇ the fourth antenna A4 ⁇ the second antenna A2 ⁇ the third antenna A3 ⁇ . Even one antenna A1, second antenna A2, third antenna A3, and fourth antenna A4 can be time-shared with respect to three antennas under measurement using one receiver 21. The phase difference can be calculated and the phase can be corrected.
- the 4-branch diversity receiver according to the fourth embodiment of the present invention is the first antenna serving as the reference antenna, as shown in FIG. A1, a second antenna A2 serving as a first antenna under measurement, a third antenna A3 serving as a second antenna under measurement, and a third antenna A4 serving as a third antenna under measurement, A part of the output of the first antenna A1 is input to the power combiner 14 via the first directional coupler 11, and a part of the output of the second antenna A2 is input to the second directional coupler 11b.
- Input via the first phase shifter 13a, and part of the output of the third antenna A3 is input via the third directional coupler 11c and the second phase shifter 13b, and the output of the fourth antenna A4.
- the second antenna A2 ⁇ the third antenna A3 using three consecutive symbol intervals S j-2 , S j-1 , S j. Since the phase difference is calculated and time-divisionally calculated for the three antennas under measurement in order of the fourth antenna A4 ⁇ the second antenna A2, the third antenna A3, and the fourth antenna In the phase correction of the antenna A4, a delay corresponding to a maximum of three symbol intervals occurred after data acquisition.
- the 4-branch diversity receiving apparatus three antennas to be measured, that is, the second antenna A2, the third antenna A3, and the fourth antenna A4 within one symbol period S j . Perform phase correction.
- the guard interval GI is received by the first antenna (reference antenna) A1, and the copy source interval T
- the first antenna A 1 is switched to the second antenna A 2
- the second antenna A 2 is switched to the third antenna A 3
- the copy source section T is switched.
- switch to the third antenna A3 ⁇ fourth antenna A4 in the middle of t 34 then switch to the fourth antenna A4 ⁇ first antenna A1 in t 41 in the middle of the copy source section T, the copy source section T
- the signals of the second antenna A2, the third antenna A3, and the fourth antenna A4 are received in a time division manner.
- the complex correlation coefficient ⁇ 2 with the copy source section T of the second antenna A2 is calculated in the first divided guard section obtained by dividing the guard section GI into three, and the guard section GI is divided into three.
- the complex correlation coefficient ⁇ 3 between the second divided guard interval and the copy source interval T of the third antenna A3 is calculated, and further, the third divided guard interval and the fourth antenna obtained by dividing the guard interval GI into three.
- the complex correlation coefficient ⁇ 4 with the copy source section T of A4 is calculated.
- the sections taking the correlations ⁇ 2 , ⁇ 3 , and ⁇ 4 for each of the second antenna A 2, the third antenna A 3, and the fourth antenna A 4 are about 3 compared to the third embodiment. However, the section length is sufficient for phase correction.
- the phase of the three antennas to be measured can be corrected in one symbol period S j , so that a higher-speed fading environment can be followed.
- the power combiner 14 includes a signal of the reference antenna A1 and a plurality of antennas A2 to be measured phase-shifted by the three phase shifters 13a, 13b, and 13c.
- the signals A3 and A4 are synthesized.
- the signal of the reference antenna A1 and the signals of the antennas under measurement A2, A3, and A4 are normally subjected to correlation calculation, they may be simply combined by the power combiner 14, but the correlation calculations ⁇ 2 , ⁇ 3 , ⁇ When 4 is not normally performed, if the power combiner 14 combines the signals, the signal deteriorates.
- signals of antennas under measurement whose correlation coefficients ⁇ 2 , ⁇ 3 , and ⁇ 4 are equal to or less than a threshold value (for example, 0.3) are not combined.
- a threshold value for example, 0.3
- the signal strength is the highest of the four antennas A1, A2, A3, and A4 without combining the signals by the power combiner 14. Choose a strong one.
- the present invention is a two-branch diversity receiver in the first embodiment, a three-branch diversity receiver in the second embodiment, and a three-branch diversity in the third and fourth embodiments.
- Each of the receiving devices has been described by way of example, but it should not be understood that the description and drawings that form part of the disclosure herein limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.
- the present invention is applicable to a multi-branch diversity receiver having a plurality of N branches of 4 branches or more. That is, although not shown in the figure, more generally, a description can be given by configuring a plurality of N branches with a reference antenna as one reference antenna and a plurality (N ⁇ 1) of antennas to be measured. (N is a positive integer of 2 or more.) In the case of this N-branch diversity receiver, as in FIG.
- a switch that switches between any of the branch outputs) a receiver that is connected to the output side of the switch and demodulates the OFDM signal, and is inserted into each of the (N ⁇ 1) measured branches.
- the OFDM signals respectively received by the antennas to be measured are phase-shifted and then output to the power combiner (N-1). And number of phase shifters, a configuration and a processing circuit.
- the arithmetic processing circuit of the N-branch diversity receiver inputs a demodulated signal from the receiver, and calculates a complex correlation coefficient between the guard interval of the reference antenna and each copy source interval of the measured branch for each symbol interval.
- the calculation of the rotation angle in the complex plane from the complex correlation coefficient, and the output of a signal to be phase-shifted by the rotation angle to the phase shifter of the corresponding antenna branch to be measured is (N ⁇ 1) Perform on all measurement branches. As described above, when the number N of branches is larger than 2, the correlation between the reference antenna and a plurality (N ⁇ 1) of antennas to be measured is sequentially obtained, and the phase is set in each branch.
- a delay corresponding to a maximum of N symbol sections occurs in the phase correction of all N branches in consideration of one symbol section for calculating the correction amount.
- N-branch diversity receiver even if there are N antennas, (N ⁇ 1) antennas are used by using one receiver 21.
- the phase difference can be corrected by calculating the phase difference in a time division manner for the antenna under measurement.
- signals of antennas under measurement whose correlation coefficients ⁇ 2 , ⁇ 3 , and ⁇ 4 are not more than a threshold (for example, 0.3) are not combined. It has been described that one of the two antennas A1, A2, A3, and A4 having the strongest signal strength is selected. The same applies to the two-branch diversity receiver described in the first embodiment, the three-branch diversity receiver described in the second embodiment, and the three-branch diversity receiver described in the third embodiment. It is.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Radio Transmission System (AREA)
Abstract
Description
図1Aに示すように、本発明の第1の実施の形態に係るダイバーシチ受信装置は、 基準アンテナとなる第1のアンテナA1と、被測定アンテナとなる第2のアンテナA2と、第1のアンテナA1及び第2のアンテナA2のそれぞれが受信したOFDM信号を電力合成する電力合成器14と、電力合成器14の出力側に接続された地上ディジタル放送チューナー15と、OFDM信号の有効シンボル区間の途中において、各シンボル区間毎に第1のアンテナA1の分岐出力と第2のアンテナA2の分岐出力とを切り替えるスイッチSと、スイッチSの出力側に接続され、OFDM信号を復調する受信機21と、第2のアンテナA2の出力側に接続され、第2のアンテナA2が受信したOFDM信号を移相させた後、電力合成器14に出力する位相器13と、受信機21から復調信号を入力し、位相器13に回転角分だけ移相させる信号を出力する演算処理回路22とを備える。第1のアンテナA1の出力側には第1の方向性結合器11が接続され、第1のアンテナA1の出力の一部をスイッチS側に分岐し、第2のアンテナA2の出力側に第2の方向性結合器12が接続され、第2のアンテナA2の出力の一部をスイッチS側に分岐している。電力合成器14には、第1のアンテナA1の出力の一部が第1の方向性結合器11を介し入力され、第2のアンテナA2の出力の一部が第2の方向性結合器12、位相器13を介し入力される。演算処理回路22としてはディジタルシグナルプロセッサ(DSP)等のマイクロプロセッサが使用可能で、受信機21の信号はAD変換されて演算処理回路22に入力され、演算処理回路22の出力信号はDA変換されて位相器13に入力される。第1のアンテナA1及び第2のアンテナA2のそれぞれの構造は、例えば、モノポールアンテナやヘリカルアンテナ等の外付けアンテナや、PIFA(planer inverted-F antenna)方式のいわゆる逆F型アンテナ、折れ曲がりモノポール方式のアンテナ、或いは配線パターンで平面バランを構成したプリント基板を利用した平面型の基板アンテナ等の内蔵アンテナが採用可能で、第1のアンテナA1及び第2のアンテナA2は円柱状の導電体棒に限定されるものではなく、平面アンテナ(パッチアンテナなど)を含めた種々のアンテナが含まれる。
図3に示すフローチャートを参照しながら、本発明の第1の実施の形態に係るダイバーシチ受信装置の動作例を説明する:
(a)先ず、ステップS101において、演算処理回路(DSP)22のアンテナ切り替え手段221が、スイッチSに信号DOを送信し、第1のアンテナA1と第2のアンテナA2のいずれかのブランチに切り替える。
φ=∠ρ (2)
(f)ステップS106で、移相手段225が、第2のアンテナA2の受信信号の位相を回転角φ分だけ逆方向に移相すれば同相受信される:
y(t)=x1(t)+x2(t)e-jφ (3)
式(3)において、x1(t)は第1のアンテナA1で受信した信号、x2(t)は第2のアンテナA2で受信した信号、y(t)はアレイ出力信号である。図1Bの各シンボル区間Sjで取得したデータ(ガード区間GIの信号とコピー元区間Tの信号)は次のシンボル区間Sj+1で位相補正量が計算され,更に次のシンボル区間Sj+2の先頭で位相器が制御され,位相補正される。即ち、図1Bの各ガード区間GIの先頭に、それぞれ位相補正を行うタイミングΦj-2,Φj-1,Φj,…を、上向きの矢印で示したように、第1の実施の形態に係るダイバーシチ受信装置では、第2のアンテナA2の受信信号の位相は、データ取得後、1個のシンボル区間分遅れて、逐次補正される。
本発明の第1の実施の形態に係るダイバーシチ受信装置においては、2ブランチダイバーシチの場合でも位相補正の反映は少なくとも1シンボル分遅延する。遅延の影響を計算機シミュレーションで確認した結果を図5に示す。図5のシミュレーションの条件は、表1に示したのと同様であるが、実用を考慮し、伝送パラメータのシンボルは、現状の放送体系(県域,固定利用)に用いられているモード3とした。
本発明の第1の実施の形態に係るダイバーシチ受信装置の方式の1つの特徴は、既存のテレビ受像機をそのまま用いて受信できることである。ローコスト化のため5.5MHzの受信帯域を2MHzに制限し、AD変換器の標本化速度も500kspsとした場合でも相関係数が誤りなく計算できることを計算機シミュレーションで確認した結果を図6~図9に示す。図6~図9に示す計算機シミュレーションの評価では、ブランチの切り替えは行わず、フェージングもかけていない。
本発明の第1の実施の形態に係るダイバーシチ受信装置で完全なキャリア同期が必要かどうか計算機シミュレーションにより確認した結果を図10及び11に示す。図10はドップラ周波数fDを0Hzにしたときのブランチ間の位相差の時間変化で、図11はドップラ周波数fDを25Hzにしたときのブランチ間の位相差の時間変化である。図10(a)及び11(a)が真の位相差、図10(b)及び11(b)がシステムで推定した位相差で、キャリア周波数と1kHz異なる局部発振器で復調している。図11に示すように、ドップラ周波数fD=25Hzでは、1シンボル遅れで位相差が出力されていることが分かる。上下の位相カーブはおおむね一致しており、第1の実施の形態に係るダイバーシチ受信装置においては完全なキャリア同期をとらなくても位相差が求められることが分かる。
ISDB-T方式の特徴は、ガード区間GI内の遅延波があっても受信品質に影響しないことである。しかし、本発明の第1の実施の形態に係るダイバーシチ受信装置では各ブランチの受信包絡線を使って位相差を求めているため、位相計算に影響を及ぼすものと考えられる。各ブランチで、ガード区間GI内のランダムな遅延を発生させ、目的波(直接波)と混信波の電界強度の対数比(DU比)が5dBの遅延波を発生させた。本発明者らは、東京・神奈川・浜松の50か所以上についてフィールドでの遅延プロファイルを測定しているが、今のところガード区間GIを超える遅延波は認められていない。又、ガード区間GI内の遅延波はしばしば散見されるが最悪でもDU比は7dB程度である。上記の条件は最悪の場合と考えて差し支えないと思われる。
上記の第1の実施の形態の説明において、簡単のため2ブランチダイバーシチ受信装置について例示的に説明したが、本発明は3ブランチダイバーシチ受信装置にも適用可能である。
各シンボル区間Sj-1,Sj,Sj+1,Sj+2,…ごとに、第2のアンテナA2→第3のアンテナA3→第2のアンテナA2→アンテナA3…の順番で位相補正をすることができるので、アンテナが、第1のアンテナA1、第2のアンテナA2及び第3のアンテナA3の3つであっても、1つの受信機21を用いて、2つの被測定アンテナに対して、時分割で位相差を計算して位相補正することができる。
第1の実施の形態では2ブランチダイバーシチ受信装置を、第2の実施の形態では3ブランチダイバーシチ受信装置を、それぞれ例示的に説明したが、本発明は4ブランチダイバーシチ受信装置にも適用可能である。第2の実施の形態で説明したとおり、アンテナは3つでも良いが、実際に使う場合は、4つのアンテナ(基準アンテナ1本、被測定アンテナ3本)を用いる4ブランチダイバーシチ受信装置とすることが多い。
重複するため、構成の図示を省略しているが、本発明の第4の実施の形態に係る4ブランチダイバーシチ受信装置は、図18に示したのと同様に、基準アンテナとなる第1のアンテナA1と、第1の被測定アンテナとなる第2のアンテナA2と、第2の被測定アンテナとなる第3のアンテナA3と、第3の被測定アンテナとなる第3のアンテナA4とを備え、電力合成器14には、第1のアンテナA1の出力の一部が第1の方向性結合器11を介し入力され、第2のアンテナA2の出力の一部が第2の方向性結合器11b、第1の位相器13aを介し入力され、第3のアンテナA3の出力の一部が第3の方向性結合器11c、第2の位相器13bを介し入力され、第4のアンテナA4の出力の一部が第4の方向性結合器11d、第3の位相器13cを介し入力され、受信機12は第1のアンテナA1、第2のアンテナA2、第3のアンテナA3及び第4のアンテナA4にスイッチSを介して接続される。
上記のように、本発明は、便宜上、第1の実施の形態で2ブランチダイバーシチ受信装置、第2の実施の形態で3ブランチダイバーシチ受信装置、第3及び第4の実施の形態では3ブランチダイバーシチ受信装置について、それぞれ例示的に説明したが、本明細書の開示の一部をなす論述及び図面は本発明を限定するものであると理解すべきではない。この開示から当業者には様々な代替実施の形態、実施例及び運用技術が明らかとなろう。
Claims (7)
- 基準アンテナとなる第1のアンテナと、
被測定アンテナとなる第2のアンテナと、
前記第1及び第2のアンテナのそれぞれが受信したOFDM信号を電力合成する電力合成器と、
前記電力合成器の出力側に接続された地上ディジタル放送チューナーと、
前記OFDM信号の有効シンボル区間の途中において、各シンボル区間毎に前記第1のアンテナの分岐出力と前記第2のアンテナの分岐出力とを切り替えるスイッチと、
前記スイッチの出力側に接続され、前記OFDM信号を復調する受信機と、
前記第2のアンテナの出力側に接続され、前記第2のアンテナが受信した前記OFDM信号を移相させた後、前記電力合成器に出力する位相器と、
前記復調信号を入力し、前記シンボル区間毎に前記第1のアンテナのガード区間と前記第2のアンテナのコピー元区間との複素相関係数を計算し、前記複素相関係数より複素面での回転角を求め、前記位相器に前記回転角分だけ移相させる信号を出力する演算処理回路
とを備えることを特徴とするダイバーシチ受信装置。 - 前記第1のアンテナから前記電力合成器に至る伝送経路の一部に挿入され、前記第1のアンテナが受信したOFDM信号の一部を前記スイッチに分岐する第1の方向性結合器と、
前記第2のアンテナから前記位相器に至る伝送経路の一部に挿入され、前記第2アンテナが受信したOFDM信号の一部を前記スイッチに分岐する第2の方向性結合器
とを更に備えることを特徴とする請求項1に記載のダイバーシチ受信装置。 - 基準アンテナと、
複数の被測定アンテナと、
前記基準アンテナ及び前記複数の被測定アンテナのそれぞれが受信したOFDM信号を電力合成する電力合成器と、
前記電力合成器の出力側に接続された地上ディジタル放送チューナーと、
前記OFDM信号の有効シンボル区間の途中において、各シンボル区間毎に前記基準アンテナの分岐出力と前記複数の被測定アンテナのいずれかの分岐出力とを切り替えるスイッチと、
前記スイッチの出力側に接続され、前記OFDM信号を復調する受信機と、
前記複数の被測定アンテナの出力側のそれぞれに接続され、前記複数の被測定アンテナがそれぞれ受信した前記OFDM信号をそれぞれ移相させた後、前記電力合成器にそれぞれ出力する複数の位相器と、
前記復調信号を入力し、前記シンボル区間毎に前記基準アンテナのガード区間と前記複数の被測定アンテナのコピー元区間のいずれかとの複素相関係数を計算し、前記複素相関係数より複素面での回転角を求め、対応する前記複数の被測定アンテナのいずれかの前記位相器に前記回転角分だけ移相させる信号を出力する処理を、前記複数の被測定アンテナのすべてに実施する演算処理回路
とを備えることを特徴とするダイバーシチ受信装置。 - 前記基準アンテナから前記電力合成器に至る伝送経路の一部に挿入され、前記基準アンテナが受信したOFDM信号の一部を前記スイッチに分岐する第1の方向性結合器と、
前記複数の被測定アンテナから前記位相器に至る複数の伝送経路の一部にそれぞれ挿入され、前記複数の第2アンテナのそれぞれが受信したOFDM信号の一部をそれぞれ前記スイッチに分岐する複数の第2の方向性結合器
とを更に備えることを特徴とする請求項3に記載のダイバーシチ受信装置。 - Nを3以上の正の整数として、前記複数の被測定アンテナの本数を(N-1)本とし、前記演算処理回路が、連続する(N-1)個の前記シンボル区間を用いて、各シンボル区間毎に前記基準アンテナのガード区間と前記複数の被測定アンテナのコピー元区間のいずれかとの複素相関係数を計算する処理を順次行い、前記複素相関係数より複素面での回転角を逐次求めることを特徴とする請求項3又は4に記載のダイバーシチ受信装置。
- Nを3以上の正の整数として、前記複数の被測定アンテナの本数を(N-1)本とし、前記演算処理回路が、前記シンボル区間の前記ガード区間及び前記コピー元区間をそれぞれ(N-1)分割し、分割された各ガード区間において、前記基準アンテナと前記複数の被測定アンテナのいずれかとの複素相関係数を計算する処理を順次行い、前記複素相関係数より複素面での回転角を逐次求めることを特徴とする請求項3又は4に記載のダイバーシチ受信装置。
- 前記演算処理回路が、前記相関係数が閾値以下となる被測定アンテナの信号は合成しないことを特徴とする請求項3~6のいずれか1項に記載のダイバーシチ受信装置。
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP10797160A EP2453588A1 (en) | 2009-07-07 | 2010-07-07 | Diversity reception device |
JP2011521948A JP5648921B2 (ja) | 2009-07-07 | 2010-07-07 | ダイバーシチ受信装置 |
US13/382,566 US8437438B2 (en) | 2009-07-07 | 2010-07-07 | Diversity reception device |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009-160982 | 2009-07-07 | ||
JP2009160982 | 2009-07-07 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011004849A1 true WO2011004849A1 (ja) | 2011-01-13 |
Family
ID=43429273
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2010/061558 WO2011004849A1 (ja) | 2009-07-07 | 2010-07-07 | ダイバーシチ受信装置 |
Country Status (4)
Country | Link |
---|---|
US (1) | US8437438B2 (ja) |
EP (1) | EP2453588A1 (ja) |
JP (1) | JP5648921B2 (ja) |
WO (1) | WO2011004849A1 (ja) |
Families Citing this family (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9220067B2 (en) | 2011-05-02 | 2015-12-22 | Rf Micro Devices, Inc. | Front end radio architecture (FERA) with power management |
WO2013175774A1 (ja) | 2012-05-22 | 2013-11-28 | パナソニック株式会社 | 送信方法、受信方法、送信装置及び受信装置 |
US10009058B2 (en) | 2012-06-18 | 2018-06-26 | Qorvo Us, Inc. | RF front-end circuitry for receive MIMO signals |
US9219594B2 (en) | 2012-06-18 | 2015-12-22 | Rf Micro Devices, Inc. | Dual antenna integrated carrier aggregation front end solution |
US20140015731A1 (en) | 2012-07-11 | 2014-01-16 | Rf Micro Devices, Inc. | Contact mems architecture for improved cycle count and hot-switching and esd |
US9143208B2 (en) | 2012-07-18 | 2015-09-22 | Rf Micro Devices, Inc. | Radio front end having reduced diversity switch linearity requirement |
US9419775B2 (en) | 2012-10-02 | 2016-08-16 | Qorvo Us, Inc. | Tunable diplexer |
US9203596B2 (en) | 2012-10-02 | 2015-12-01 | Rf Micro Devices, Inc. | Tunable diplexer for carrier aggregation applications |
US9078211B2 (en) | 2012-10-11 | 2015-07-07 | Rf Micro Devices, Inc. | Power management configuration for TX MIMO and UL carrier aggregation |
EP2930871B1 (en) * | 2012-12-07 | 2018-03-07 | Sun Patent Trust | Signal generation method, transmission device, reception method, and reception device |
US9172441B2 (en) | 2013-02-08 | 2015-10-27 | Rf Micro Devices, Inc. | Front end circuitry for carrier aggregation configurations |
US9444671B2 (en) * | 2013-06-13 | 2016-09-13 | Hitachi Kokusai Electric Inc. | Antenna direction adjustment method and OFDM reception device |
US10050694B2 (en) | 2014-10-31 | 2018-08-14 | Skyworks Solution, Inc. | Diversity receiver front end system with post-amplifier filters |
GB2534968B (en) * | 2014-10-31 | 2020-01-08 | Skyworks Solutions Inc | A receiving system |
GB2536085B (en) * | 2014-10-31 | 2019-10-23 | Skyworks Solutions Inc | A receiving system |
DE102015220967B4 (de) * | 2014-10-31 | 2022-08-11 | Skyworks Solutions, Inc. | Diversitätsempfänger in einem Frontend-System mit Schalternetzwerk |
US9893752B2 (en) | 2014-10-31 | 2018-02-13 | Skyworks Solutions, Inc. | Diversity receiver front end system with variable-gain amplifiers |
US9385765B2 (en) | 2014-10-31 | 2016-07-05 | Skyworks Solutions, Inc. | Diversity receiver front end system with phase-shifting components |
US9485001B2 (en) | 2014-10-31 | 2016-11-01 | Skyworks Solutions, Inc. | Diversity receiver front end system with switching network |
US10009054B2 (en) | 2015-05-28 | 2018-06-26 | Skyworks Solutions, Inc. | Impedance matching integrous signal combiner |
TWI658707B (zh) | 2017-12-14 | 2019-05-01 | 財團法人工業技術研究院 | 通訊系統及其運作方法 |
TWI658708B (zh) * | 2017-12-14 | 2019-05-01 | 財團法人工業技術研究院 | 通訊系統、協調裝置及其控制方法 |
US10992419B1 (en) * | 2020-03-12 | 2021-04-27 | Nxp B.V. | Wireless communications device and method for performing an angle measurement |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005348278A (ja) * | 2004-06-07 | 2005-12-15 | Kojima Press Co Ltd | 所望波到来方向推定装置 |
JP2008066948A (ja) * | 2006-09-06 | 2008-03-21 | Advanced Telecommunication Research Institute International | アダプティブアレーアンテナ受信装置 |
JP2008160357A (ja) * | 2006-12-22 | 2008-07-10 | Kojima Press Co Ltd | 車両用ofdm受信装置 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3944422B2 (ja) | 2002-06-28 | 2007-07-11 | 株式会社ケンウッド | ダイバーシティ受信機 |
EP1557962A4 (en) * | 2002-10-28 | 2011-06-15 | Mitsubishi Electric Corp | DIVERSITY RECEIVING DEVICE AND CORRESPONDING METHOD |
JP2004282476A (ja) * | 2003-03-17 | 2004-10-07 | Sharp Corp | アンテナ装置、およびアンテナ装置を備えた電子機器 |
JP4403877B2 (ja) * | 2004-05-20 | 2010-01-27 | 株式会社豊田中央研究所 | ダイバーシチ受信における振幅の時間変動補償方法及び装置、マルチキャリアダイバーシチ受信におけるシンボル内時間変動補償方法及び装置 |
JP2009060178A (ja) * | 2007-08-29 | 2009-03-19 | Sharp Corp | ダイバーシティ装置 |
US8194623B2 (en) * | 2008-06-27 | 2012-06-05 | Ntt Docomo, Inc. | Evolving-type user resource structure/channelization with enhanced diversity for OFDMA based time-varying channels |
-
2010
- 2010-07-07 JP JP2011521948A patent/JP5648921B2/ja not_active Expired - Fee Related
- 2010-07-07 EP EP10797160A patent/EP2453588A1/en not_active Withdrawn
- 2010-07-07 US US13/382,566 patent/US8437438B2/en not_active Expired - Fee Related
- 2010-07-07 WO PCT/JP2010/061558 patent/WO2011004849A1/ja active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005348278A (ja) * | 2004-06-07 | 2005-12-15 | Kojima Press Co Ltd | 所望波到来方向推定装置 |
JP2008066948A (ja) * | 2006-09-06 | 2008-03-21 | Advanced Telecommunication Research Institute International | アダプティブアレーアンテナ受信装置 |
JP2008160357A (ja) * | 2006-12-22 | 2008-07-10 | Kojima Press Co Ltd | 車両用ofdm受信装置 |
Also Published As
Publication number | Publication date |
---|---|
US20120099682A1 (en) | 2012-04-26 |
US8437438B2 (en) | 2013-05-07 |
JPWO2011004849A1 (ja) | 2012-12-20 |
JP5648921B2 (ja) | 2015-01-07 |
EP2453588A1 (en) | 2012-05-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5648921B2 (ja) | ダイバーシチ受信装置 | |
JP4167464B2 (ja) | 車載デジタル通信受信装置 | |
KR20010082733A (ko) | 안테나 신호의 위상 제어 합산 기능을 갖는 안테나다이버시티 시스템 | |
US8781421B2 (en) | Time-domain diversity combining of signals for broadcast receivers | |
JP2006157663A (ja) | 移動体用ofdm受信装置 | |
JP5347120B2 (ja) | アンテナ装置およびそれを備えた受信機 | |
WO2006106920A1 (ja) | 受信装置、信号処理回路および受信システム | |
JP2006304205A (ja) | アンテナ位相較正装置及びそれを用いた追尾アンテナ装置 | |
JP2006186421A (ja) | Ofdmダイバーシチ受信装置 | |
JP4317335B2 (ja) | ダイバーシティ受信機 | |
US8116414B2 (en) | Diversity receiver and diversity reception method | |
JP2014060591A (ja) | 受信装置及び通信装置並びに通信システム | |
JP2001028561A (ja) | デジタルテレビジョン放送受信装置および送受信システム | |
JP3857009B2 (ja) | マルチキャリア無線受信装置およびマルチキャリア無線伝送装置 | |
JP2006217399A (ja) | 受信装置 | |
JP3650334B2 (ja) | デジタル放送受信装置 | |
JP3550326B2 (ja) | デジタル放送受信機 | |
JP2008060913A (ja) | ダイバーシチ受信装置 | |
JP5509672B2 (ja) | ダイバーシチ受信装置及びダイバーシチ受信方法 | |
JP5401726B2 (ja) | アンテナ装置およびそれを備えた受信機 | |
JP4621143B2 (ja) | ダイバーシティ受信装置 | |
JP2009033497A (ja) | 受信装置 | |
JP2007274726A (ja) | 車載デジタル信号受信装置、およびダイバーシティシステム | |
JP7289600B2 (ja) | 無線受信装置 | |
JP2008160357A (ja) | 車両用ofdm受信装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10797160 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011521948 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13382566 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13382566 Country of ref document: US |
|
REEP | Request for entry into the european phase |
Ref document number: 2010797160 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010797160 Country of ref document: EP |