Radio, radio system, and radio method

Abstract

To provide a wireless device, a wireless system, and a wireless method that can quickly converge cancellation of interference waves.SOLUTION: A wireless device combines a wireless signal b and an interference wave canceller signal c that cancels an interference wave for each channel by a second CPL 6 to cancel the interference wave when the interference wave canceller signal c is generated by an interference wave canceller 10, and updates the interference wave canceller signal generated by the interference wave canceller 10 using a residual signal e whose gain is controlled to keep the received power of the desired wave constant by a second AGC 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a radio device that communicates using multi-channel radio signals, and more particularly to a radio device, a radio system, and a radio method that eliminate multi-channel interference waves. [Background technology]

[0002] [Prior Art] In conventional wireless systems, an automatic gain control (AGC) circuit is used in the reception processing of a wireless device to correct the reception power to a constant level in order to prevent a drop in the reception power. Furthermore, some wireless systems use multiple channels for communication, and in such cases, processing is performed to cancel interference waves for each of the multiple channels.

[0003] [Conventional radio: Figure 3] A radio device used in a conventional wireless system will be described with reference to Fig. 3. Fig. 3 is a schematic diagram of the configuration of a conventional radio device. As shown in FIG. 3, a conventional radio basically comprises an antenna 1, a first coupler (CPL) 2, an analog / digital converter (A / D) 3, an interference wave detection unit 4, a delay unit 5, a second coupler (CPL) 6, a digital / analog converter (D / A) 7, a first automatic gain control circuit (AGC) 8, an analog / digital converter (A / D) 9, an interference wave canceller 10, and a demodulation unit 30. Incidentally, an interference wave canceller 10 is provided for each of a plurality of channels, and outputs from the interference wave cancellers 10 are integrated and input to the D / A 7.

[0004] In a conventional wireless device, an interference wave detector 4 detects an interference wave signal a from a signal b received by an antenna 1, an interference wave canceller 10 generates a cancellation signal (canceller signal) c that cancels the interference wave, combines this with the received signal by a second CPL 6, and outputs a residual signal d to a first AGC 8. Here, although the interference wave has been cancelled, the interference wave still remains in the residual signal d, and the residual signal d contains both the desired wave and the interference wave. The configuration and operation of the interference wave canceller 10 will be described later.

[0005] The first AGC 8 controls the gain so as to follow the change in the residual signal (desired signal and interference signal) in order to secure the dynamic range of the A / D 9 . The gain-controlled residual signal e is input to the interference wave canceller 10, and a cancellation signal c for canceling the interference wave is updated based on the residual signal e, and is combined in the second CPL 6 via the D / A 7. The updated interference wave cancellation signal c is repeatedly combined with the received signal to converge the canceller, remove the interference wave from the received signal, and the signal from which the interference wave has been removed is demodulated by demodulator 30.

[0006] [Conventional interference canceller: Figure 4] A conventional interference wave canceller 10 will be described with reference to Fig. 4. Fig. 4 is a schematic diagram showing the configuration of a conventional interference wave canceller. As shown in FIG. 4, the conventional interference wave canceller 10 includes quadrature detectors (Q-DET) 11 and 12, a delay adjustment unit 13, a weight update unit 14, an adaptive filter 15, and a quadrature modulator (Q-MOD) 16.

[0007] The Q-DET 11 inputs the interference wave signal (interference wave frequency) a from the interference wave detection unit 4 and the digitally converted received signal b from the A / D 3, performs quadrature detection, and outputs the quadrature detection signal to the adaptive filter 15 and the delay adjustment unit 13. The delay adjustment unit 13 delays the quadrature detection signal from the Q-DET 11 in accordance with the signal delays in the delay unit 5 , the second CPL 6 , the first AGC 8 , and the A / D 9 .

[0008] The Q-DET 12 receives the digitally converted residual signal e from the A / D 9 and the interference signal a from the interference detector 4, performs quadrature detection, and outputs the quadrature detection signal to the weight updater 14. The weight updater 14 updates the filter weights of the adaptive filter 15 so that the quadrature detection signal from the delay adjuster 13 coincides with the quadrature detection signal of the residual signal e from the A / D 9 .

[0009] The adaptive filter 15 is an FIR (Finite Impulse Response) filter, which is a digital filter having a finite-time impulse response, and generates a quadrature detection signal for canceling (eliminating) the interference wave using the weight value set by the weight update unit 14. The Q-MOD 16 performs quadrature modulation on the quadrature detection signal from the adaptive filter 15 and outputs it to the D / A 7 as an interference wave cancellation signal c. By the above-mentioned configuration and operation of the interference wave canceller 10, an interference wave cancellation signal c for canceling an interference wave is generated.

[0010] [Related Technology] As a related prior art, there is the "AGC circuit" disclosed in Japanese Patent Laid-Open Publication No. 11-195941 (Patent Document 1). Patent Document 1 discloses an AGC circuit having a variable gain amplifier that obtains a desired wave power and an interference wave power, and performs gain control that follows fluctuations in the desired wave power without following the interference wave power. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Publication No. 11-195941 Summary of the Invention [Problem to be solved by the invention]

[0012] However, in a radio device having a conventional AGC circuit, when canceling interference waves on multiple channels, there is a problem in that the convergence time in the interference wave canceller becomes slower as convergence progresses.

[0013] Specifically, because the interference wave is larger than the desired wave, as the cancellation convergence progresses, the interference wave in the remaining signal (desired wave and interference wave) after cancellation rapidly attenuates and becomes smaller. As a result, the difference between the desired wave and the interference wave in the remaining signal becomes smaller, and if the adaptive filter is adjusted based only on that difference, the convergence time becomes long, which is a problem.

[0014] Incidentally, Patent Document 1 does not disclose a configuration for generating an interference wave canceller signal using a residual signal whose gain is controlled so as to keep the received power of a desired wave constant when removing an interference wave.

[0015] The present invention has been made in view of the above circumstances, and has an object to provide a radio device, a radio system, and a radio method that can quickly converge on the cancellation of interference waves. [Means for solving the problem]

[0016] The present invention, which aims to solve the above-mentioned problems of the conventional example, is a radio device that removes interference waves from multi-channel radio signals, from, An interference canceller signal that cancels interference for each channel A residual signal is obtained by synthesizing the wireless signal with the interference wave canceller signal, and To keep the received power of the desired signal constant Control the gain of the residual signal. The interference canceller signal is updated using a gain-controlled residual signal.

[0017] The present invention is characterized in that, in the above-mentioned radio device, it comprises an AGC circuit which controls the gain of the residual signal so as to keep the received power of the desired wave constant, and the AGC circuit has a desired wave detection unit which detects the desired wave from the residual signal, a calculation unit which calculates an average power value from the detected desired wave, and a multiplier which multiplies the residual signal by the reciprocal of the average power value.

[0018] The present invention is a radio system comprising the radio device described above.

[0019] The present invention is a wireless method for removing interference waves from multi-channel wireless signals, which includes generating an interference wave canceller signal for canceling interference waves for each channel from a received wireless signal, synthesizing the interference wave canceller signal with the wireless signal to obtain a residual signal, residual The gain of the residual signal is controlled so as to keep the received power of the desired wave in the signal constant, and the interference wave canceller signal is updated using the residual signal whose gain has been controlled. Effect of the Invention

[0020] According to the present invention, there is provided a radio device for removing interference waves from a multi-channel radio signal, the radio device comprising: from, An interference canceller signal that cancels interference for each channel A residual signal is obtained by synthesizing the wireless signal with the interference wave canceller signal, and To keep the received power of the desired signal constant Control the gain of the residual signal. Since this radio device updates the interference wave canceller signal using a gain-controlled residual signal, the interference wave is cancelled based on the gain-controlled residual signal so as to keep the received power of the desired wave constant. This has the effect of optimizing the level of the interference wave and enabling the cancellation of the interference wave to converge quickly. [Brief description of the drawings]

[0021] [Figure 1] FIG. 2 is a schematic diagram of the configuration of the radio device. [Diagram 2] FIG. 2 is a schematic diagram of the configuration of a second AGC. [Diagram 3] FIG. 1 is a schematic diagram illustrating the configuration of a conventional wireless device. [Figure 4] FIG. 1 is a schematic diagram illustrating the configuration of a conventional interference wave canceller. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. [Outline of the embodiment] A radio according to an embodiment of the present invention (this radio) is a radio that removes interference waves from multi-channel radio signals, and when removing interference waves by combining an interference wave canceller signal that cancels the interference waves for each channel with a received radio signal, the interference wave canceller signal is updated using a residual signal whose gain is controlled to keep the received power of the desired wave constant.Since the interference waves are canceled based on the residual signal whose gain is controlled to keep the received power of the desired wave constant, the level of the interference waves can be optimized and the cancellation of the interference waves can be converged quickly.

[0023] Moreover, a wireless system according to an embodiment of the present invention (the present system) includes a plurality of the above-mentioned present wireless devices, and can quickly converge on canceling interference waves and achieve stable communications.

[0024] [This radio: Figure 1] This radio device will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the configuration of this radio device. As shown in FIG. 1, this radio basically comprises an antenna 1, a first coupler (CPL) 2, an analog / digital converter (A / D) 3, an interference wave detection unit 4, a delay unit 5, a second coupler (CPL) 6, a digital / analog converter (D / A) 7, a first automatic gain control circuit (AGC) 8, an analog / digital converter (A / D) 9, an interference wave canceller 10, a second automatic gain control circuit (AGC) 20, and a demodulation unit 30. As in the conventional case, an interference wave canceller 10 is provided for each of a plurality of channels, and outputs from the interference wave cancellers 10 are integrated and input to the D / A 7.

[0025] [Each part] Each part of this radio device will now be described in detail. The antenna 1 receives multi-channel radio signals. The first CPL 2 distributes the signal received by the antenna 1 to the A / D 3 and delay unit 5 . The A / D 3 converts the signal from the first CPL 2 from analog to digital and outputs the signal to the interference wave detection unit 4. In addition, the signal b digitally converted by the A / D 3 is branched and output to the interference wave canceller 10 as well.

[0026] The interference wave detector 4 detects an interference wave (U wave) from the digital signal b from the A / D 3, and outputs an interference wave signal (interference wave frequency) a to the interference wave canceller . The delay unit 5 delays the analog signal from the first CPL 3 by the time required for the interference wave canceller 10 to cancel the interference wave, and outputs the delayed signal to the second CPL 6 .

[0027] The second CPL 6 combines the analog signal from the delay unit 5 with the interference wave canceller signal (cancellation signal) c from the D / A 7 , and outputs a residual signal d after cancellation to the first AGC 8 . The D / A 7 converts the interference wave canceller signal c from the interference wave canceller 10 from digital to analog and outputs the signal to the second CPL 6 .

[0028] The first AGC 8 controls the gain of the residual signal (desired signal and interference signal) after cancellation from the second CPL 6 so as to follow changes in the residual signal in order to ensure the dynamic range of the A / D 9, and outputs the signal to the A / D 9. The A / D 9 converts the automatic gain controlled residual signal from the first AGC 8 from analog to digital and outputs it to the second AGC 20 .

[0029] As explained in FIG. 4, the interference wave canceller 10 generates an interference wave canceller signal c for canceling the interference wave detected by the interference wave detection unit 4 based on a residual signal d that is gain-controlled so as to keep the reception power of the desired wave from the second AGC 20 constant, and outputs the interference wave canceller signal c to the D / A 7.

[0030] The second AGC 20 performs automatic gain control on the residual signal d from the A / D 9 so that the received power of the desired wave becomes constant, and outputs the gain-controlled residual signal e to the interference wave canceller 10 and demodulation section 30 . The demodulation unit 30 demodulates the residual signal e that has been gain-controlled by the second AGC 20 .

[0031] In other words, the residual signal that has been gain-controlled by the second AGC 20 so that the received power of the desired wave is constant contains an interference wave, and the interference wave of the residual signal that is rapidly attenuated by the cancellation process can be brought to an appropriate level based on the constant received power of the desired wave. This involves the second AGC 20 keeping the received power of the desired wave constant, changing (updating) the level of the interference wave to an appropriate level based on that, and performing cancellation processing.

[0032] [Second AGC20: Figure 2] Next, the second AGC 20 will be described with reference to Fig. 2. Fig. 2 is a schematic diagram of the configuration of the second AGC. As shown in FIG. 2, the second AGC 20 includes a desired wave detection section 21, a desired wave average power calculation section 22, and a multiplier .

[0033] The desired wave detection unit 21 receives the digitally converted residual signal from the A / D 9, detects a desired wave (D wave) of a frequency that is recognized in advance for a specific channel, and outputs the detected signal to the desired wave average power calculation unit 22. Desired wave average power calculation section 22 receives the desired wave (D wave) detected by desired wave detection section 21, calculates the average power value (Dp) of the desired wave, and outputs it to multiplier .

[0034] The multiplier 23 multiplies the digitally converted residual signal from the A / D 9 by the inverse of the average power value (Dp) from the desired wave average power calculation unit 22, and outputs a gain-controlled residual signal e for the desired wave to the interference wave canceller 10 and the demodulation unit 30.

[0035] [Operation] Next, the operation of this radio device will be described. In this radio device, the interference wave detection unit 4 detects the interference wave signal a from the signal b received by the antenna 1, the interference wave canceller 10 generates a canceller signal c that cancels the interference wave, combines it with the signal received by the second CPL 6, and outputs the residual signal d to the first AGC 8.

[0036] The first AGC 8 controls the gain so as to follow the change in the residual signal (desired signal and interference signal) in order to secure the dynamic range of the A / D 9 . The gain-controlled residual signal e is A / D converted and then gain-controlled by a second AGC 20 so that the received power of the desired wave is constant. The gain-controlled residual signal e is input to an interference wave canceller 10, and a canceller signal c that cancels the interference wave is updated based on the residual signal e, and is then combined by a second CPL 6 via a D / A 7. The updated interference wave canceller signal c is repeatedly combined with the received signal to cause the canceller to converge, the interference wave is removed from the received signal, and the signal from which the interference wave has been removed is demodulated by demodulator 30 .

[0037] In addition, by providing multiple wireless devices in this system, it is possible to quickly cancel interference waves in each wireless device, thereby achieving stable communications.

[0038] [Effects of the embodiment] According to this radio device, which is a radio device that removes interference waves from multi-channel radio signals, an interference wave canceller signal c that cancels the interference wave for each channel is generated by the interference wave canceller 10 for the received radio signal b, and when the radio signal b and the interference wave canceller signal c are synthesized by the second CPL 6 to remove the interference wave, the second AGC 20 updates the interference wave canceller signal using a residual signal e whose gain is controlled so as to keep the reception power of the desired wave constant. Therefore, since the interference wave is canceled based on the residual signal e whose gain is controlled so as to keep the reception power of the desired wave constant, it is possible to optimize the level of the interference wave and achieve the effect of quickly converging the cancellation of the interference wave.

[0039] Furthermore, according to the present system, since a plurality of the present wireless devices are provided, it is possible to quickly converge the cancellation of interference waves in each wireless device, thereby achieving stable communications. [Industrial Applicability]

[0040] The present invention is suitable for a radio device, a radio system, and a radio method that can quickly converge on the cancellation of an interference wave. [Explanation of symbols]

[0041] REFERENCE SIGNS LIST 1...antenna, 2...first coupler (CPL), 3...analog / digital converter (A / D), 4...interference wave detection section, 5...delay section, 6...second coupler (CPL), 7...digital / analog converter (D / A), 8...first automatic gain control circuit (AGC), 9...analog / digital converter (A / D), 10...interference wave canceller, 11, 12...quadrature detector (Q-DET), 13...delay adjustment section, 14...weight update section, 15...adaptive filter, 16...quadrature modulator (Q-MOD), 20...second automatic gain control circuit (AGC), 21...desired wave detection section, 22...desired wave average power calculation section, 23...multiplier, 30...demodulation section

Claims

1. A radio device for removing interference waves from multi-channel radio signals, comprising: A radio device comprising: a first receiving unit that receives a first signal from a second receiving channel of the first radio signal; a second receiving unit that receives a second signal from the second receiving channel of the first radio signal; a third receiving unit that receives a second signal from the first receiving channel of the first radio signal; a fourth receiving unit that receives a second signal from the first receiving channel of the first radio signal; a fifth receiving unit that receives a third signal from the first receiving channel of the first radio signal;

2. an AGC circuit for controlling a gain of a residual signal so as to keep the received power of the desired wave constant; 2. The radio device according to claim 1, wherein the AGC circuit comprises a desired wave detection unit that detects the desired wave from the residual signal, a calculation unit that calculates an average power value from the detected desired wave, and a multiplier that multiplies the residual signal by the reciprocal of the average power value.

3. 3. A radio system comprising the radio device according to claim 1.

4. A wireless method for removing interference waves from a multi-channel wireless signal, comprising: A wireless method comprising the steps of: generating an interference wave canceller signal that cancels interference waves for each channel from a received wireless signal; synthesizing the interference wave canceller signal with the wireless signal to obtain a residual signal; controlling a gain of the residual signal so as to keep constant the received power of a desired wave in the residual signal; and updating the interference wave canceller signal using the gain-controlled residual signal.

Images