JP4631732B2 - Wireless receiver - Google Patents

Description

  The present invention relates to a radio reception apparatus that receives a radio signal having a pulse-like signal at a predetermined cycle at a timing synchronized with the cycle.

  In recent years, as one of high-speed wireless transmission methods, attention has been paid to an ultra wide band (UWB) communication method that performs ultra-wideband communication using a pulse signal sequence composed of pulse signals synchronized with a predetermined cycle timing. Yes. As one aspect of UWB communication, there is known one in which communication is performed using a pulse signal sequence including an extremely short pulse signal such as a pulse width of 1 nsec (nanoseconds) or less without using a carrier wave (for example, Patent Documents). 1).

There is also known a radio apparatus that detects the reception intensity of a radio signal and discriminates the radio signal from noise depending on whether or not the reception intensity exceeds a predetermined determination level so as not to receive noise (for example, , See Patent Document 2).
Japanese National Patent Publication No. 10-508725 Japanese Patent Laid-Open No. 10-32504

  By the way, as in the wireless device described in Patent Document 2 described above, the reception strength of a wireless signal is detected, the wireless signal and noise are determined depending on whether the reception strength exceeds a predetermined determination level, and the noise is received. It is conceivable to reduce the influence of noise by applying a technique for avoiding this to the above-described UWB receiver. However, UWB communication does not use a carrier wave, and uses an extremely short pulse signal such as a pulse width of 1 nsec or less. Therefore, the transmission power spectral density is very low compared to other wireless communication systems, and the noise signal level is low. There is a disadvantage that the difference between the signal level of the radio signal pulse and the radio signal pulse is small, and it is difficult to set the determination level capable of discriminating between the radio signal and the noise.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a radio receiving apparatus that can improve the discrimination accuracy between radio signals and noise and improve the reliability of communication. To do.

  In order to achieve the above-described object, a radio reception apparatus according to the present invention is a radio reception apparatus that receives a radio signal having a pulse-like signal at a predetermined cycle at a timing synchronized with the cycle, A receiving unit for receiving a signal, a noise receiving unit for acquiring a level of the signal received by the receiving unit at a timing different from the period, and an average of the levels of a plurality of signals received by the noise receiving unit A noise floor value generating unit that generates a value as a noise floor value indicating a background noise level and outputs the first noise floor value, and a first noise floor value output by the noise floor value generating unit, A determination unit that determines whether the signal received by the reception unit is the radio signal or noise; and the reception unit receives the radio signal by the determination unit And when it is determined, it is characterized in that it comprises a demodulator for demodulating the radio signal received by the receiving unit.

  Further, in the above-described wireless reception device, the noise floor value generation unit may calculate an average value of the remaining signal levels excluding at least the maximum value among the levels of the plurality of signals received by the noise reception unit. It is generated as a floor value.

  Further, in the above-described wireless reception device, the noise floor value generation unit further calculates an average value of the levels of the remaining signals excluding a minimum value among the levels of the plurality of signals received by the noise reception unit, It is generated as a noise floor value.

  Further, in the above-described wireless reception device, the noise floor value generation unit may further reduce a signal level that is next to the maximum value and next to the minimum value among the levels of the plurality of signals received by the noise reception unit. An average value of the remaining signal levels excluding the signal level is generated as the noise floor value.

  Further, in the above-described wireless reception device, the noise floor value generation unit periodically generates a new noise floor value.

  Further, in the above-described wireless reception device, a storage unit that stores a plurality of first noise floor values generated by the noise floor value generation unit, and an average value of the plurality of first noise floor values stored by the storage unit. An average processing unit that generates an average noise floor value, and the determination unit receives the reception unit based on an average noise floor value obtained by the average processing unit instead of the first noise floor value. It is characterized in that it is determined whether the received signal is the radio signal or noise.

  Further, in the above-described wireless reception device, the noise reception unit includes a plurality of integration circuits that respectively integrate the levels of the signals received by the reception unit at a plurality of different timings, and integrated values in the plurality of integration circuits Are output to the noise floor value generation unit as levels of the plurality of signals.

  Moreover, in the above-described wireless reception device, the noise floor value generation unit newly generates the noise floor value as a second noise floor value, and the second noise floor value exceeds a predetermined range set in advance. The noise floor value is newly generated as the second noise floor value again, and when the second noise floor value is within the range, the second noise floor value is output as the first noise floor value. It is a feature.

  In the radio reception apparatus having such a configuration, a radio signal having a pulsed signal at a predetermined cycle is received by the reception unit, and the level of the signal received at a timing different from the cycle is acquired by the noise reception unit. The noise floor value generation unit generates an average value of the levels of the plurality of signals received by the noise reception unit as a noise floor value indicating the background noise level, and outputs the noise floor value as a first noise floor value. Then, based on the first noise floor value output from the noise floor value generation unit, the determination unit determines whether the signal received by the reception unit is a radio signal or noise, and the determination unit receives the reception unit. When it is determined that the radio signal is received in step S1, the demodulation unit demodulates the radio signal received by the reception unit.

  As a result, the radio signal and the noise are discriminated based on the first noise floor value generated by the noise floor value generator, and the radio signal is demodulated when it is determined that the radio signal is received by the receiver. Therefore, it is possible to reduce erroneous demodulation of noise as a radio signal and improve communication reliability. In addition, the noise floor value is generated by averaging the signal levels acquired a plurality of times at a timing different from the pulse period in the radio signal, and the level of the pulse signal in the radio signal is acquired to affect the noise floor value. Therefore, the reliability of communication can be improved by improving the accuracy of the noise floor value and improving the discrimination accuracy between the radio signal and noise.

  Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.

(First embodiment)
FIG. 1 is a block diagram illustrating an example of a configuration of a wireless reception device 1 according to an embodiment of the present invention. 1 includes an antenna 2 (receiver), a pulse demodulator 3, an AD converter 4, a reception controller 5, a demodulator 6, a reference clock generator 7, and phase control. Part 8. The antenna 2 receives a radio signal RF by UWB communication.

  The pulse demodulator 3 is a circuit that demodulates the radio signal received by the antenna 2, an amplifier 31 that amplifies the signal received by the antenna 2, a filter 32 that filters the signal amplified by the amplifier 31, and a filter 32. Are provided with an amplifier 33 for amplifying the signal filtered by the amplifier 33, and a detector 34 for detecting the signal amplified by the amplifier 33 to generate a detection signal RS and outputting it to the AD converter 4 and the demodulator 6. .

  The AD converter 4 converts the detection signal RS detected by the pulse demodulator 3 into a digital signal and outputs it as a signal level value Vs.

  The demodulator 6 acquires data from the detection signal RS according to the control signal from the reception controller 5, and outputs received data RD representing the data to the outside. The reference clock generation unit 7 is configured using, for example, a crystal oscillator, generates a clock signal having the same cycle as the cycle of the pulse signal in UWB communication, and outputs the clock signal to the phase control unit 8.

  The phase control unit 8 outputs a gate signal GT for controlling the operation timing of the pulse demodulation unit 3 to the amplifier 31 and the amplifier 33 based on the clock signal output from the reference clock generation unit 7. Specifically, the phase control unit 8 has a pulse width equal to or slightly larger than the pulse width of the pulse signal in UWB communication, for example, a pulse signal set to 10 nsec, for example, in a cycle of the pulse signal in UWB communication, for example, 500 nsec cycle. The signal is output to the amplifier 31 and the amplifier 33 as the gate signal GT. In addition, the phase control unit 8 changes the timing of the pulse signal in the radio signal RF in accordance with the control signal from the reception control unit 5.

  The amplifier 31 and the amplifier 33 amplify the signal in synchronization with the timing of the pulse signal in the gate signal GT, and do not perform signal amplification at other timings. Thereby, the pulse demodulator 3 detects a signal synchronized with the cycle timing of the pulse signal in the radio signal RF received by the antenna 2 as a radio signal pulse to generate a detection signal RS.

  FIG. 2 is a block diagram illustrating an example of the configuration of the reception control unit 5 used in the wireless reception device 1 according to the first embodiment of the present invention. The reception control unit 5 illustrated in FIG. 2 includes a noise floor value generation unit 51 and a determination unit 52.

  The noise floor value generation unit 51 is a circuit that generates a signal detected by the pulse demodulation unit 3 when a pulse signal in UWB communication is not received by the antenna 2, that is, a noise floor value Vn representing a signal level of background noise. The noise floor value Vn is generated and stored by acquiring and averaging the signal level value Vs output from the AD converter 4 a plurality of times. The noise floor value generation unit 51 includes, for example, a storage circuit 501 (noise reception unit), a maximum value determination unit 502, a minimum value determination unit 503, a subtractor 504, an average processing unit 505, a noise floor storage unit 506, a timer 507, and A control unit 508 is provided.

  The storage circuit 501 is a storage circuit configured using a plurality of, for example, ten registers, and stores a plurality of signal level values Vs output from the AD converter 4 in response to a control signal from the control unit 508. . The maximum value determination unit 502 outputs the maximum value among the plurality of signal level values Vs stored in the storage circuit 501 to the subtracter 504. The minimum value determination unit 503 outputs the minimum value among the plurality of signal level values Vs stored in the storage circuit 501 to the subtractor 504.

  The subtractor 504 sums up the plurality of signal level values Vs stored in the storage circuit 501, and outputs a plurality of maximum values output from the maximum value determination unit 502 and minimum values output from the minimum value determination unit 503. Subtract from the total value of the signal level value Vs, and output to the average processing unit 505. The average processing unit 505 is a circuit unit for averaging a plurality of signal level values Vs, and is configured by, for example, a division circuit, and a plurality of signals output from the subtracter 504 according to a control signal from the control unit 508. In order to discriminate noise and UWB radio signal pulse from an average value obtained by dividing the total value excluding the maximum value and minimum value in the signal level value Vs by a number that is two less than the number of registers in the storage circuit 501. The noise floor value Vn is output to the noise floor storage unit 506.

  The noise floor storage unit 506 is a storage circuit configured using, for example, a register, and stores the noise floor value Vn output from the average processing unit 505 as the first noise floor value Vn1 according to the control signal from the control unit 508. To do. The timer 507 is a timer that generates a control timing for generating a time element for shifting the reception timing by the pulse demodulator 3 or generating a timing for acquiring the detection signal RS from the pulse demodulator 3.

  The control unit 508 is configured using, for example, a state machine, generates a control signal according to the timing signal output from the timer 507, changes the output timing of the gate signal GT by the phase control unit 8, and stores the control signal. A plurality of, for example, 10 signal level values Vs are stored in the circuit 501, the noise floor value Vn is calculated in the average processing unit 505, or the noise floor value Vn is set as the first noise floor value Vn1 in the noise floor storage unit 506. Remember it.

  The determination unit 52 determines whether the signal received by the antenna 2 is a radio signal or noise based on the first noise floor value Vn1 generated by the noise floor value generation unit 51, and is a radio signal. When the control signal is determined, the control signal for starting the demodulation operation to the demodulation unit 6 is output. The determination unit 52 includes, for example, an addition value storage unit 521, a magnification setting unit 522, a multiplier 523, an adder 524, and a comparator 525.

  The added value storage unit 521 is a storage unit that stores 4.6σ that is a value obtained by multiplying the standard deviation σ of the noise signal level by 4.6 times. FIG. 3 is an explanatory diagram for explaining a method for obtaining the standard deviation σ of the noise signal level. The standard deviation σ of the noise signal level is determined by the wireless receiver 1 when there is no signal when UWB wireless communication is not performed in an environment where the wireless receiver 1 is used, for example, an environment where home appliances are operating in a house. It is obtained by calculating the standard deviation σ of the received signal level.

  FIG. 4 is an explanatory diagram for explaining the relationship between signal pulses and noise when a UWB wireless signal is received. As shown in FIG. 4, the noise is in the range of the noise floor value Vn ± σ. The signal level Vs of the signal pulse is | Vn−Vs |> 4.6σ, that is, the difference between the noise floor value Vn and the signal level Vs of the signal pulse exceeds 4.6 times the noise deviation σ. Thus, it is known that signal pulses can be distinguished from noise and can be normally communicated. Therefore, the standard deviation σ of the noise signal level is obtained in advance by experiments, and 4.6σ is stored in the added value storage unit 521 in advance.

  The magnification setting unit 522 is an operation reception unit that allows the user to set the magnification α of 4.6σ stored in the addition value storage unit 521. For example, a rotary switch that is an example of a plurality of dip switches or multi-contact switches. Etc. Then, 4.6σ stored in the addition value storage unit 521 and the magnification α received by the magnification setting unit 522 are multiplied by the multiplier 523, and the multiplication value is stored in the noise floor storage unit 506. The first noise floor value Vn1 is added by the adder 524 and output to the comparator 525 as the threshold value Vth.

  The comparator 525 compares the threshold value Vth output from the adder 524 with the signal level value Vs output from the AD converter 4. If the signal level value Vs exceeds the threshold value Vth, the signal level value Vs is A control signal for determining that the signal is a radio signal and causing the demodulator 6 to start a demodulation operation is output. On the other hand, if the signal level value Vs does not exceed the threshold value Vth, the comparator 525 determines that the signal level value Vs is noise, and does not output a control signal that causes the demodulation unit 6 to start the demodulation operation.

  Thereby, it is determined whether the signal received by the receiving unit is a radio signal or noise. The threshold value Vth is obtained as Vth = Vn + 4.6σ × α. For example, if the user sets the magnification α to 1 using the magnification setting unit 522, Vth = Vn + 4.6σ, for example, an environment with a high noise level. When the wireless receiver 1 is used, the threshold value Vth can be increased if the user increases the magnification α, for example, if the magnification α is set to 1.5 or 2 or the like. It becomes possible to discriminate between a signal and noise.

  When receiving the control signal for starting the demodulation operation from the reception control unit 5, the demodulation unit 6 demodulates the detection signal RS output from the pulse demodulation unit 3 and outputs it as reception data RD to the outside.

  Next, the operation of the wireless reception device 1 configured as described above will be described. FIG. 5 is a signal waveform diagram for explaining an example of the operation of the wireless reception device 1. In FIG. 5, the pulse signal cycle of UWB communication is set to 500 nsec, for example, and the pulse width is set to 10 nsec. In the radio signal RF, pulses P 1, P 2, and P 3 indicate an example of a UWB communication pulse signal received by the antenna 2.

  First, the phase control unit 8 outputs a high-level control pulse G1 having a pulse width of 10 nsec based on the clock signal output from the reference clock generation unit 7 to the amplifier 31 and the amplifier 33 as the gate signal GT. In FIG. 5, the timing of the pulse P1 coincides with the timing of the control pulse G1. Then, the pulse P1 is amplified by the amplifier 31, unnecessary frequency components are removed by the filter 32, amplified by the amplifier 33, further detected by the detector 34, and detected as the detection signal RS to the AD converter 4 and the demodulator 6. Is output.

  In this case, since the amplifier 31 and the amplifier 33 do not operate at the timing when the pulse P1 does not exist, noise signals other than the pulse P1 in the radio signal RF are removed from the detection signal RS. Further, at the timing of the pulse P1, the radio signal RF has a pulse P1 that is a pulse signal of UWB communication, so that the output level of the detection signal RS output from the pulse demodulator 3 as indicated by reference symbol A is The communication signal level is increased.

  Next, the radio signal RF is converted into a digital value by the AD converter 4 and output to the storage circuit 501 as the signal level value Vs. Then, the storage circuit 501 stores the signal level value Vs in synchronization with the timing of the control pulse G1 according to the control signal from the control unit 508.

  Next, a control signal is output from the control unit 508 to the phase control unit 8 to cause the pulse demodulation unit 3 to perform a pulse demodulation operation of the radio signal RF at a timing different from the pulse signal cycle of UWB communication, for example, a 500 nsec cycle, The timing of the next control pulse G2 in the gate signal GT is delayed by, for example, 10 nsec, which is the same as the pulse width of the gate signal GT, and output to the amplifier 31 and the amplifier 33 by the phase control unit 8. Then, since the timing of the pulse P2 and the timing of the control pulse G2 do not coincide with each other, the pulse P2 is not demodulated by the pulse demodulator 3, and the noise signal level in the radio signal RF is detected as the detection signal RS to the AD converter 4. Is output. In this case, when the timing of the control pulse G2 is immediately after the pulse P2, as indicated by the reference symbol B, the signal level of the detection signal RS may decrease due to the influence of the pulse P2. As described above, the phenomenon that the signal level of the detection signal RS decreases is more remarkable as the signal level of the pulse P2 is larger.

  Next, the radio signal RF is converted into a digital value by the AD converter 4 and output to the storage circuit 501 as the signal level value Vs. Then, the storage circuit 501 stores the signal level value Vs of the detection signal RS, that is, the noise signal level, in synchronization with the timing of the control pulse G2 in accordance with the control signal from the control unit 508.

  Next, a control signal is output from the control unit 508 to the phase control unit 8 to cause the pulse demodulation unit 3 to perform the pulse demodulation operation of the radio signal RF again at a timing different from the pulse signal cycle of UWB communication, for example, a 500 nsec cycle. The timing of the next control pulse G2 in the gate signal GT is further delayed from the control pulse G3 by, for example, 10 nsec, which is the same as the pulse width of the gate signal GT, and output to the amplifier 31 and the amplifier 33. . Then, since the timing of the control pulse G3 does not coincide with the timing of the pulse P3 by 20 nsec, the pulse P3 is not demodulated by the pulse demodulator 3, and the noise signal level in the radio signal RF is detected as the detection signal RS by the AD converter. 4 is output.

  Then, the AD converter 4 converts the radio signal RF into a digital value and outputs it to the storage circuit 501 as a signal level value Vs. Further, the storage circuit 501 stores the signal level value Vs of the detection signal RS, that is, the noise signal level in synchronization with the timing of the control pulse G3 in accordance with the control signal from the control unit 508.

  As described above, the control operation is performed a plurality of times by the control unit 508 so that the memory circuit 501 stores the signal level value Vs of the detection signal RS as the noise signal level in synchronization with the timing of the control pulse G2, for example, the storage circuit 501. The number of registers is repeated 10 times, and 10 signal level values Vs of the detection signal RS are stored in the storage circuit 501.

  Next, the maximum value determination unit 502 acquires the maximum value of the signal level values Vs of the plurality of detection signals RS stored in the storage circuit 501 and outputs the maximum value to the subtractor 504. Further, the minimum value determination unit 503 acquires the minimum value in the signal level value Vs of the plurality of detection signals RS stored in the storage circuit 501 and outputs the minimum value to the subtractor 504. Then, the subtracter 504 sums up the plurality of signal level values Vs stored in the storage circuit 501, and the maximum value output from the maximum value determination unit 502 and the minimum value output from the minimum value determination unit 503. Is subtracted from the total value of the plurality of signal level values Vs and output to the average processing unit 505.

  Next, the average processing unit 505 calculates the total value excluding the maximum value and the minimum value of the plurality of signal level values Vs output from the subtractor 504 according to the control signal from the control unit 508. An average value obtained by dividing by 2 less than the number of registers, for example, 8 is output to the noise floor storage unit 506 as a noise floor value Vn for discriminating between noise and UWB radio signal pulses, and stored in the noise floor. The first noise floor value Vn1 is stored in the unit 506.

  Next, the first noise floor value Vn1 stored in the noise floor storage unit 506 is added to 4.6σ by the adder 524 and output to the comparator 525 as the threshold value Vth. Then, the comparator 525 compares the signal level value Vs with the threshold value Vth, and if the signal level value Vs exceeds the threshold value Vth, the signal level value Vs is determined to be a radio signal and demodulated from the comparator 525. A control signal for starting the demodulation operation to the unit 6 is output. Further, when a control signal for starting a demodulation operation is output from the comparator 525 to the demodulator 6, the timing of the gate signal GT is synchronized with the cycle timing of the pulse signal in the radio signal by the phase controller 8, and the demodulator 6, the detection signal RS output from the pulse demodulator 3 is demodulated and output to the outside as received data RD.

  On the other hand, if the signal level value Vs does not exceed the threshold value Vth, the comparator 525 determines that the signal level value Vs is noise and does not output a control signal that causes the demodulation unit 6 to start the demodulation operation. It is possible to reduce erroneous demodulation with a radio signal and improve communication reliability.

  Here, as indicated by reference symbol A, when the timings of the pulse P1 and the control pulse G1 coincide, the signal level of the pulse P1 instead of the noise signal level is stored in the storage circuit 501 as the signal level value Vs, When the averaging process is performed as it is, the noise floor value Vn increases and the accuracy of the first noise floor value Vn1 decreases. However, the maximum value determination unit 502 and the subtracter 504 exclude the maximum value among the plurality of signal level values Vs stored in the storage circuit 501, that is, the signal level value of the pulse P <b> 1 and sudden high level noise. Therefore, the accuracy of the first noise floor value Vn1 can be improved, and the discrimination accuracy between the radio signal and the noise can be improved.

  Further, as indicated by reference symbol B, the timing of the control pulse G2 is immediately after the pulse P2, and particularly when the signal level of the pulse P2 is high, the noise floor value Vn decreases and the accuracy of the noise floor value Vn decreases. To do. However, since the minimum value determination unit 503 and the subtracter 504 exclude the minimum value in the plurality of signal level values Vs stored in the storage circuit 501, that is, the signal level value immediately after the pulse P2, the accuracy of the noise floor value Vn is excluded. And the discrimination accuracy between the radio signal and the noise can be improved.

  Note that a configuration without the minimum value determination unit 503 or a configuration without the maximum value determination unit 502 and the minimum value determination unit 503 may be employed. Even in this case, since the radio signal RF is received a plurality of times at a timing different from the pulse signal cycle of UWB communication and the obtained detection signal RS is averaged, the UWB in the radio signal RF received by the antenna 2 By reducing the influence of communication pulse signals and sudden high-level noise, the accuracy of the noise floor value Vn can be improved, and the discrimination accuracy between radio signals and noise can be improved.

  The generation operation of the noise floor value Vn may be executed when the wireless reception device 1 is activated, or a new noise floor value Vn may be generated periodically and repeatedly. When the generation operation of the noise floor value Vn is executed when the wireless reception device 1 is activated, for example, if there is low-frequency background noise that fluctuates at a cycle of 100 msec, such low-frequency noise is generated. The noise floor value Vn is generated without taking into account the influence of. Then, for example, when the wireless reception device 1 is activated when the level of low frequency noise is high, the noise floor value Vn is set high. As a result, communication may not be possible if the pulse signal of UWB communication is low. Further, for example, when the radio receiving apparatus 1 is activated when the level of low frequency noise is low, the noise floor value Vn is set low, and as a result, when the noise level rises in that cycle, background noise is pulsed in UWB communication. It may be judged as a signal and communication may become impossible.

  However, when a new noise floor value Vn is generated periodically, for example, every 10 msec, the influence of such low frequency noise can be eliminated.

(Second Embodiment)
Next, a radio reception apparatus according to the second embodiment of the present invention will be described. The wireless reception device 1a according to the second embodiment of the present invention is different from the wireless reception device 1 according to the first embodiment in the configuration of the noise floor value generation unit 51a. FIG. 6 is a block diagram illustrating an example of the configuration of the noise floor value generation unit 51a. The noise floor value generation unit 51a illustrated in FIG. 6 is different from the noise floor value generation unit 51 illustrated in FIG. 2 in that the maximum value side two sample detection unit 502a, the minimum value side two sample detection unit 503a, and the subtractor 504a are configured. Different.

  The maximum value side two-sample detection unit 502a outputs the maximum value among the plurality of signal level values Vs stored in the storage circuit 501 and the next largest value to the subtracter 504a. The minimum-value-side two-sample detection unit 503a outputs the minimum value of the plurality of signal level values Vs stored in the storage circuit 501 and the next smallest value to the subtractor 504a.

  The subtracter 504 sums up the plurality of signal level values Vs stored in the storage circuit 501, and outputs the maximum value and the next largest value after the maximum value output from the maximum value side two-sample detection unit 502 a, and the minimum value side. The minimum value output from the 2-sample detection unit 503a and the next smallest value after the minimum value are subtracted from the total value of the plurality of signal level values Vs and output to the average processing unit 505.

  Since the other configuration is the same as that of the reception control unit 5 shown in FIG. 2, the description thereof will be omitted, and the characteristic points of the present embodiment will be described below. FIG. 7 is a signal waveform diagram for explaining the operation of the noise floor value generation unit 51a shown in FIG.

  First, the phase control unit 8 outputs a high-level control pulse G4 having a pulse width of 10 nsec based on the clock signal output from the reference clock generation unit 7 to the amplifier 31 and the amplifier 33 as the gate signal GT. In FIG. 7, the timing of the control pulse G4 overlaps with the timing of the first half of the pulse P4. Then, the first half of the pulse P4 is amplified by the amplifier 31, unnecessary frequency components are removed by the filter 32, amplified by the amplifier 33, further detected by the detector 34, and detected by the AD converter 4 and the demodulation. Is output to the unit 6.

  In this case, the first half of the pulse P4 is demodulated by the pulse demodulator 3 and output to the AD converter 4 as the detection signal RS, so that the detection signal RS output from the pulse demodulator 3 as indicated by the reference symbol D. The output level increases to indicate the communication signal level.

  Next, the AD converter 4 converts the radio signal RF into a digital value and outputs the digital value to the storage circuit 501. Then, the memory circuit 501 stores the signal level value Vs of the detection signal RS in synchronization with the timing of the control pulse G4 according to the control signal from the control unit 508.

  Next, a control signal is output from the control unit 508 to the phase control unit 8 to cause the pulse demodulation unit 3 to perform the demodulation operation of the radio signal RF at a timing different from the pulse signal cycle of UWB communication, for example, a 500 nsec cycle. The timing of the next control pulse G5 in the gate signal GT is delayed by, for example, 10 nsec, which is the same as the pulse width of the gate signal GT, and output to the amplifier 31 and the amplifier 33. Then, since the timing of the control pulse G5 overlaps with the latter half of the pulse P5, the latter half of the pulse P5 is demodulated by the pulse demodulator 3 as the detection signal RS as in the timing of the control pulse G4 described above. Since it is output to the AD converter 4, the output level of the detection signal RS output from the pulse demodulator 3 increases as shown by the reference symbol E, indicating the communication signal level.

  Next, the radio signal RF is converted into a digital value by the AD converter 4 and output to the storage circuit 501 as the signal level value Vs. Then, the memory circuit 501 stores the signal level value Vs of the detection signal RS, that is, the noise signal level, in synchronization with the timing of the control pulse G5 in accordance with the control signal from the control unit 508.

  In this case, since the first half and the second half of the UWB communication pulse signal are stored in the storage circuit 501 as the signal level value Vs of the detection signal RS, the noise floor value generation unit 51 shown in FIG. Even if the maximum value is excluded by the determination unit 502, one of the first half and the second half of the pulse signal of UWB communication remains, so that the generation accuracy of the noise floor value Vn is lowered.

  However, in the noise floor value generation unit 51a shown in FIG. 6, the maximum value and the maximum value among the plurality of signal level values Vs stored in the storage circuit 501 by the maximum value side two-sample detection unit 502a and the subtractor 504a. Therefore, both the first half and the second half of the pulse signal of UWB communication can be excluded, the accuracy of the noise floor value Vn is improved, and the discrimination accuracy between the radio signal and the noise is eliminated. Can be improved.

  Similarly, when the timing of the control pulse in the gate signal GT overlaps with the first half of the signal level lowering portion immediately after the pulse signal of UWB communication, the signal level is higher than the noise floor due to the influence of the communication signal pulse. The signal level value Vs that has decreased may be stored in the two storage circuits 501, but in the noise floor value generation unit 51a illustrated in FIG. 6, the minimum value side two sample detection unit 503a and the subtractor 504a Since the minimum value and the next smallest value of the plurality of signal level values Vs stored in the storage circuit 501 are excluded, the first half of the portion where the signal level is lowered due to the influence of the pulse signal of UWB communication Both the latter half can be excluded, the accuracy of the noise floor value Vn can be improved, and the discrimination accuracy between the radio signal and noise can be improved.

(Third embodiment)
Next, a radio receiving apparatus according to the third embodiment of the present invention will be described. The wireless reception device 1b according to the third embodiment of the present invention is different from the wireless reception device 1a according to the second embodiment in the configuration of the noise floor value generation unit 51b. FIG. 8 is a block diagram illustrating an example of the configuration of the noise floor value generation unit 51b. The noise floor value generation unit 51b illustrated in FIG. 8 is different from the noise floor value generation unit 51a illustrated in FIG. 6 between the average processing unit 505 and the noise floor storage unit 506, and the average value temporary storage unit 509 and the average processing unit. 510 (average processing unit) is different.

  The average value temporary storage unit 509 is configured using, for example, a plurality of registers, and stores a plurality of noise floor values Vn output from the average processing unit 505 according to a control signal from the control unit 508. The average processing unit 510 averages a plurality of noise floor values Vn stored in the average value temporary storage unit 509 according to a control signal from the control unit 508, and stores the average noise floor value Vnn in the noise floor storage unit 506. .

  And the average noise floor value Vnn memorize | stored in the noise floor memory | storage part 506 is output to the determination part 52, and the determination part 52 is received with the antenna 2 using the average noise floor value Vnn instead of the noise floor value Vn. It is determined whether the received signal is a radio signal or noise.

  Since the other configuration is the same as that of the noise floor value generation unit 51a shown in FIG. 6, the description thereof will be omitted, and the characteristic points of the present embodiment will be described below. For example, when the background noise level temporarily increases, for example, when the noise floor value Vn is generated at the timing when a noise generation source such as a microwave oven is used, the set level of the noise floor value Vn increases. When such a high level noise floor value Vn is set, a pulse signal of low level UWB communication may be judged as noise and may not be received.

  However, in the noise floor value generation unit 51b illustrated in FIG. 8, the storage circuit 501, the maximum value side two sample detection unit 502a, the minimum value side two sample detection unit 503a, and the subtractor 504a are controlled according to the control signal from the control unit 508. The noise floor value Vn is generated a plurality of times by the average processing unit 505, the plurality of noise floor values Vn are stored in the average value temporary storage unit 509, and the plurality of noise floor values Vn are obtained from the control unit 508. The average processing unit 510 averages according to the control signal, and the average value is stored in the noise floor storage unit 506 as the average noise floor value Vnn. Therefore, the background noise level is detected over a long period of time, and the average noise floor value Vnn is detected. As a result, even if the background noise level temporarily increases, the average noise floor value It is possible to reduce the influence of such a temporary noise to nn.

  Since it is determined whether the signal received by the antenna 2 is a radio signal or noise based on the average noise floor value Vnn, it is possible to improve the discrimination accuracy between the radio signal and noise.

(Fourth embodiment)
Next, a radio reception apparatus according to the fourth embodiment of the present invention is described. FIG. 9 is a block diagram illustrating an example of a configuration of a wireless reception device 1c according to the fourth embodiment of the present invention. The wireless reception device 1c according to the fourth embodiment of the present invention is different from the wireless reception device 1 (1a, 1b) illustrated in FIG. 1 in the following points.

  That is, the pulse demodulator 3a of the wireless reception device 1c shown in FIG. Further, instead of the AD converter 4, a plurality of integration blocks 10-1 to 10-n are provided. The integration block 10-1 includes an integration circuit 9-1 and an AD converter 4-1. Similarly, the integration blocks 10-2 to 10-n include the integration circuits 9-2 to 9-n and the AD converter 4. -2 to 4-n. The integrating circuits 9-1 to 9-n integrate the signal levels received by the antenna 2 and detected by the pulse demodulator 3a at a plurality of different timings, respectively, and the integrated values are converted into the AD converter 4- 1 to 4-n are converted into digital values, respectively, and output to the reception control unit 5a as signal level values Vs1 to Vsn.

  The reception control unit 5a is different from the reception control unit 5 shown in FIG. 2 (the noise floor value generation unit 51a shown in FIG. 6 and the noise floor value generation unit 51b shown in FIG. 8). The difference is that the signal level values Vs1 to Vsn output from 1 to 10-n are stored as a plurality of signal level values. In this case, the integration blocks 10-1 to 10-n and the storage circuit 501 correspond to an example of a noise receiving unit.

  The phase control unit 8a integrates gate signals GT1 to GTn having different timings for controlling the integration timings of the integration circuits 9-1 to 9-n based on the clock signal output from the reference clock generation unit 7, respectively. Output to 9-1 to 9-n.

  Since other configurations are the same as those of the wireless reception device 1 (1a, 1b) shown in FIG. 1, the description thereof will be omitted, and the operation of the wireless reception device 1c shown in FIG. 9 will be described below. FIG. 10 is a signal waveform diagram for explaining the operation of the wireless reception device 1c. FIG. 10 shows an example in which the period of the pulse signal in UWB communication is, for example, 50 nsec, and the gate signals GT1 to GTn having high-level control pulses whose pulse width is set to 10 nsec and the timing is shifted by 10 nsec are in phase. It is output from the control unit 8a to the integrating circuits 9-1 to 9-n.

  In FIG. 10, the timing of the pulse P6 in the detection signal RS coincides with the timing of the control pulse in the gate signal GT1, and the pulse P6 is integrated by the integration block 10-1, and the integration value is set as the signal level value Vs1. The data is output to the reception control unit 5a and the demodulation unit 6.

  In addition, since the pulse P6 and the control pulse in the gate signals GT2 to GTn are at different timings, the detection signal RS, that is, the noise signal level at the timing different from the pulse P6 is caused by the integration blocks 10-2 to 10-n. The integrated values are output to the reception control unit 5a as signal level values Vs2 to Vsn.

  Then, the storage circuit 501 in the reception control unit 5a stores the signal level values Vs2 to Vsn as a plurality of signal level values indicating the noise signal level, and the noise is the same as the noise floor value generation unit 51 (51a, 51b) described above. Floor value Vn (or average noise floor value Vnn) is generated and output to determination unit 52.

  Since other operations are the same as those of the wireless reception device 1 (1a, 1b) shown in FIG.

  Thereby, since the plurality of signal level values Vs2 to Vsn indicating the noise signal level acquired at a timing different from the signal pulse using the plurality of integration blocks 10-2 to 10-n are acquired by the parallel operation, The time for acquiring the signal level values Vs2 to Vsn can be shortened, and the generation process of the noise floor value Vn (Vnn) can be speeded up.

  In addition, although each control pulse in the gate signals GT1 to GTn has shown an example in which the timing is shifted by the same time as the pulse width, each control pulse may partially overlap, or an interval between each control pulse. May be vacant.

  Further, for example, using a plurality of integration blocks, for example, integration blocks 10-1 and 10-2, the timing of each control pulse in the gate signals GT1 and GT2 is shifted for each pulse signal period in the UWB radio to have different phase timings. Thus, a plurality of signal level values Vs1 and Vs2 indicating the noise signal level may be acquired over a plurality of cycles and stored in the storage circuit 501. Specifically, as shown in FIG. 11, the timing of each control pulse in the gate signals GT1 and GT2 is changed by, for example, 10 nsec, which is the same as the pulse width, and, for example, for each period of the pulse signal in the detection signal RS, the time T1, As indicated by T2, by delaying the timing of each control pulse in the gate signals GT1 and GT2 by the time obtained by adding the pulse widths of the control pulses in the gate signals GT1 and GT2 indicated by broken lines, a noise signal is generated over a plurality of periods. A plurality of signal level values Vs1 and Vs2 indicating the level may be acquired and stored in the storage circuit 501.

(Fifth embodiment)
Next, a radio receiving apparatus according to the fifth embodiment of the present invention is described. The wireless reception device 1d according to the fifth embodiment of the present invention is different from the wireless reception device 1 according to the first embodiment in the configuration of the noise floor value generation unit 51c. FIG. 12 is a block diagram illustrating an example of the configuration of the noise floor value generation unit 51c. The noise floor value generation unit 51c illustrated in FIG. 12 does not include the maximum value determination unit 502, the minimum value determination unit 503, and the subtractor 504, and the noise floor value generation unit 51 illustrated in FIG. The difference is that a unit 511, an initial value storage unit 512, a threshold storage unit 513, and a comparator 514 are provided. Further, the operation of the control unit 508c is different.

  Then, the average processing unit 505 outputs the average value of the plurality of signal level values Vs stored in the storage circuit 501 to the update noise floor storage unit 511 as the noise floor value Vn. The update noise floor storage unit 511 is a storage circuit configured by using, for example, a register, and is provided between the average processing unit 505 and the noise floor storage unit 506, and the noise floor value Vn output from the average processing unit 505. Is stored as the second noise floor value Vn2 and output to the noise floor storage unit 506 and the comparator 514.

  The initial value storage unit 512 and the threshold value storage unit 513 are configured using nonvolatile storage elements such as an EEPROM (Electrically Erasable and Programmable Read Only Memory). The initial value storage unit 512 stores in advance a first noise floor value Vn1 to be stored in the noise floor storage unit 506 as an initial value after activation of the wireless reception device 1d. The initial value of the first noise floor value Vn1 stored in the initial value storage unit 512 is, for example, the noise floor value Vn generated by the average processing unit 505 when there is no external noise when the wireless reception device 1d is shipped from the factory. Can be used.

  Whether the threshold value storage unit 513 is generated by the influence of temporary noise based on whether or not the second noise floor value Vn2 output from the update noise floor storage unit 511 is within a predetermined range. The threshold value Vnx for determining whether or not is stored in advance and the threshold value Vnx is output to the comparator 514. As the threshold value Vnx, for example, an initial value of the first noise floor value Vn1 stored in the initial value storage unit 512 is experimentally set to a fluctuation range of a general noise floor value in a use environment such as a house or an office. This value, for example, a value obtained by adding a value of about 3 dB can be used.

  The noise floor storage unit 506 stores the second noise floor value Vn2 output from the update noise floor storage unit 511 as the first noise floor value Vn1 according to the control signal from the control unit 508c, and also compares the comparator 514. And output to the determination unit 52. The comparator 514 compares the second noise floor value Vn2 output from the update noise floor storage unit 511 with the threshold value Vnx output from the threshold value storage unit 513, and outputs the comparison result to the control unit 508c. .

  The control unit 508c further stores the second noise floor value Vn2 generated by the average processing unit 505 in the update noise floor storage unit 511, and outputs the second noise floor value Vn2 output from the update noise floor storage unit 511. And the threshold value Vnx output from the threshold value storage unit 513 are compared by the comparator 514. Then, if the second noise floor value Vn2 exceeds the threshold value Vnx, the control unit 508c further increases the noise floor value Vn by the average processing unit 505 based on the signal level value Vs newly stored in the storage circuit 501. Is generated and stored as the second noise floor value Vn2 by the noise floor storage unit 511 for update.

  In addition, as a result of the comparison between the second noise floor value Vn2 and the threshold value Vnx by the comparator 514, the control unit 508c updates the noise floor storage unit 511 if the second noise floor value Vn2 is within the range of the threshold value Vnx or less. The noise floor storage unit 506 stores the second noise floor value Vn2 output from the first noise floor value Vn1 and outputs it to the determination unit 52.

  Since other configurations and operations are the same as those of the wireless reception device 1, the description thereof is omitted, and the operation of the wireless reception device 1d according to the present embodiment will be described below. First, for example, when a power switch (not shown) is turned on and the wireless reception device 1d is activated, the first noise floor value Vn1 stored in the initial value storage unit 512 according to a control signal from the control unit 508c. Is stored in the noise floor storage unit 506 and output to the determination unit 52, and the radio signal RF is received and demodulated in the same manner as the radio reception device 1.

  Next, in the same manner as the wireless receiver 1, the wireless signal RF received by the antenna 2 according to the gate signal GT from the phase controller 8 is pulse demodulated by the pulse demodulator 3, and the signal level is converted by the AD converter 4. The value Vs is acquired, a plurality of signal level values Vs are stored by the storage circuit 501, and the noise floor value Vn is generated by the average processing unit 505 based on the plurality of signal level values Vs, and the noise floor storage unit for update To 511.

  The noise floor value Vn output from the average processing unit 505 is stored as the second noise floor value Vn2 by the update noise floor storage unit 511 and is output to the noise floor storage unit 506 and the comparator 514. . Further, the comparator 514 compares the second noise floor value Vn2 output from the update noise floor storage unit 511 with the threshold value Vnx output from the threshold value storage unit 513, and outputs the comparison result to the control unit 508c. Is done.

  Then, if the second noise floor value Vn2 exceeds the threshold value Vnx, the average processing unit 505 further performs the processing based on the signal level value Vs newly stored in the storage circuit 501 according to the control signal from the control unit 508c. A new noise floor value Vn is generated and stored as the second noise floor value Vn2 by the update noise floor storage unit 511.

  Further, as a result of the comparison between the second noise floor value Vn2 and the threshold value Vnx by the comparator 514, if the second noise floor value Vn2 is within the range of the threshold value Vnx or less, the update is performed according to the control signal from the control unit 508c. The second noise floor value Vn2 output from the noise floor storage unit 511 is stored as the first noise floor value Vn1 by the noise floor storage unit 506 and also output to the determination unit 52.

  In the wireless reception device 1d, as shown in FIG. 5, the pulse period of the radio signal RF and the control pulse period in the gate signal GT are set at different timings, and therefore, for example, the timing of the radio signal RF and the gate signal GT As a result, the noise floor value Vn is generated not based on the noise signal level but based on the signal level of the radio signal pulse, and the noise floor value Vn is prevented from increasing. It is like that.

  On the other hand, when high-level noise occurs temporarily, for example, when high-level noise occurs due to the use of a microwave oven, an electromagnetic cooker, or the like, high-level noise is received wirelessly over a plurality of cycles of the control pulse in the gate signal GT. Since it is received by the device 1d, the noise floor value Vn increases. For example, in the wireless reception device 1 using the noise floor value generation unit 51 shown in FIG. 2, the noise floor value Vn increased by the temporary noise is stored in the noise floor storage unit 506 as the first noise floor value Vn1. When used as a determination criterion in the determination unit 52, the first noise floor value Vn1 remains increased even when the use of a device that becomes a noise source such as a microwave oven ends and the noise level decreases. As a result, the determination unit 52 determines that the signal pulse is noise, and may not receive the radio signal RF correctly.

  However, in the wireless reception device 1d using the noise floor value generation unit 51c illustrated in FIG. 12, the noise floor value Vn obtained by the average processing unit 505 is stored as it is in the noise floor storage unit 506 as the first noise floor value Vn1. Instead, it is temporarily stored in the noise floor storage unit 511 for updating as the second noise floor value Vn2. Then, the second noise floor value Vn2 is compared with the threshold value Vnx by the comparator 514. When the second noise floor value Vn2 exceeds the range equal to or lower than the threshold value Vnx, that is, for example, a general noise floor value in a house or office If it exceeds the fluctuation range, it can be considered that a high level of noise is temporarily generated by the operation of a device such as a microwave oven or an electromagnetic cooker. In such a case, the noise floor storage unit 506 Since the new noise floor value Vn is generated again as the second noise floor value Vn2 without updating the first noise floor value Vn1 stored in the first noise floor value Vn1, the first noise floor value Vn2 is generated by temporary high-level noise. It is suppressed that Vn1 increases and the radio signal RF cannot be received correctly.

  Further, when the use of a device that becomes a high level noise source such as a microwave oven is finished and the noise level is lowered, the second noise floor value Vn2 is lowered, so that the second noise floor value by the comparator 514 is reduced. As a result of the comparison between Vn2 and the threshold value Vnx, if the second noise floor value Vn2 falls within the range of the threshold value Vnx or less, the second noise floor value Vn2 output from the update noise floor storage unit 511 is converted into the noise floor storage unit. By 506, it is memorize | stored as 1st noise floor value Vn1, and it is output to the determination part 52, and the discrimination | determination precision of a radio signal and noise improves, Therefore The reliability of communication can be improved.

  Note that the threshold storage unit 513 stores in advance, for example, a threshold Vnx that is obtained by adding a fluctuation range of a general noise floor value in a usage environment such as a house or office to the first noise floor value Vn1. As shown, for example, such a fluctuation range is stored, and the initial value of the first noise floor value Vn1 stored in the initial value storage unit 512 and the fluctuation range are added by, for example, an adder. You may output to the comparator 514.

  In addition, the threshold storage unit 513 stores a value obtained by adding a fluctuation range of a general noise floor value in the usage environment of the wireless reception device 1d to the first noise floor value Vn1 as an upper limit value of the threshold, and subtracts it. And the comparator 514 outputs to the control unit 508c whether or not the second noise floor value Vn2 is within the range indicated by the lower limit value and the upper limit value. Good.

  Further, instead of storing the threshold value Vnx in the threshold value storage unit 513, the threshold value Vnx may be set using a rotary switch which is an example of one or a plurality of dip switches or multi-contact switches.

  The update noise floor storage unit 511 is an average of any one of the noise floor value generation unit 51 illustrated in FIG. 2, the noise floor value generation unit 51 a illustrated in FIG. 6, and the noise floor value generation unit 51 b illustrated in FIG. 8. The noise floor value Vn obtained by the processing unit 505 may be stored.

  Further, the second noise floor value Vn2 output from the update noise floor storage unit 511 illustrated in FIG. 12 is stored in the average value temporary storage unit 509 illustrated in FIG. 8 instead of the noise floor value Vn, and illustrated in FIG. The noise floor storage unit 506 may be configured to store the average noise floor value Vnn obtained by the average processing unit 510 shown in FIG. 8 as the first noise floor value Vn1 and to output to the determination unit 52.

  Further, the storage circuit 501 illustrated in FIG. 12 may store the signal level values Vs1 to Vsn obtained by the plurality of integration blocks 10-1 to 10-n illustrated in FIG. 9 as a plurality of signal level values. Good.

It is a block diagram which shows an example of a structure of the radio | wireless receiving apparatus which concerns on one Embodiment of this invention. It is a block diagram which shows an example of a structure of the reception control part used for the radio | wireless receiver which concerns on the 1st Embodiment of this invention. It is explanatory drawing for demonstrating the acquisition method of standard deviation (sigma) of a noise signal level. It is explanatory drawing for demonstrating the relationship between the signal pulse and noise at the time of receiving a UWB radio signal. It is a signal waveform diagram for demonstrating an example of operation | movement of the radio | wireless receiver which concerns on the 1st Embodiment of this invention. It is a block diagram which shows an example of a structure of the noise floor value production | generation part used for the radio | wireless receiver which concerns on the 2nd Embodiment of this invention. It is a signal waveform diagram for demonstrating operation | movement of the noise floor value production | generation part shown in FIG. It is a block diagram which shows an example of a structure of the noise floor value production | generation part used for the radio | wireless receiver which concerns on the 3rd Embodiment of this invention. It is a block diagram which shows an example of a structure of the radio | wireless receiver which concerns on the 4th Embodiment of this invention. FIG. 10 is a signal waveform diagram for explaining an example of the operation of the wireless reception device shown in FIG. 9. FIG. 10 is a signal waveform diagram for explaining an example of the operation of the wireless reception device shown in FIG. 9. It is a block diagram which shows an example of a structure of the noise floor value production | generation part used for the radio | wireless receiver which concerns on the 5th Embodiment of this invention.

Explanation of symbols

1, 1a, 1b, 1c, 1d Wireless receiver 2 Antenna 3, 3a Pulse demodulator 4 AD converter 4-1 to 4-n AD converter 5, 5a Reception controller 6 Demodulator 7 Reference clock generator 8, 8a Phase control unit 9-1 to 9-n Integration circuit 10-1 to 10-n Integration block 31, 33 Amplifier 32 Filter 34 Detector 51, 51a, 51b, 51c Noise floor value generation unit 52 Determination unit 501 Storage circuit 502 Maximum value determination unit 502a Maximum value side 2 sample detection unit 503 Minimum value determination unit 503a Minimum value side 2 sample detection unit 504, 504a Subtractors 505, 510 Average processing units 508, 508c Control unit 509 Average value temporary storage unit 511 For updating Noise floor storage unit 512 Initial value storage unit 513 Threshold storage unit 514 Comparator 521 Addition value storage unit 522 Magnification setting unit 523 Multiplier 5 4 adder 525 comparator Vn noise floor value Vnn average noise floor value

Claims (8)

A wireless reception device that receives a wireless signal having a pulsed signal at a predetermined cycle at a timing synchronized with the cycle,
A receiver for receiving the radio signal;
A noise receiving unit for acquiring a level of a signal received by the receiving unit at a timing different from the period;
A noise floor value generating unit that generates an average value of the levels of a plurality of signals received by the noise receiving unit as a noise floor value indicating a background noise level, and outputs the first noise floor value;
A determination unit that determines whether a signal received by the reception unit is the radio signal or noise based on the first noise floor value output by the noise floor value generation unit;
A radio receiving apparatus comprising: a demodulating unit that demodulates the radio signal received by the receiving unit when the determining unit determines that the radio signal is received by the receiving unit. The noise floor value generation unit generates, as the noise floor value, an average value of residual signal levels excluding at least a maximum value among a plurality of signal levels received by the noise reception unit. The wireless receiver according to claim 1. The noise floor value generation unit further generates an average value of remaining signal levels excluding a minimum value as the noise floor value among a plurality of signal levels received by the noise reception unit. The wireless receiver according to claim 2. The noise floor value generation unit further includes, among the levels of the plurality of signals received by the noise reception unit, a remaining signal excluding a signal level that is the second largest next to the maximum value and a signal level that is the second smallest next to the minimum value. The wireless reception device according to claim 3, wherein an average value of levels is generated as the noise floor value. The wireless reception device according to claim 1, wherein the noise floor value generation unit periodically generates a new noise floor value. A storage unit for storing a plurality of first noise floor values output by the noise floor value generation unit;
An average processing unit that generates an average value of a plurality of first noise floor values stored by the storage unit as an average noise floor value;
The determination unit determines whether the signal received by the reception unit is the radio signal or noise based on an average noise floor value obtained by the average processing unit instead of the first noise floor value. The wireless receiver according to claim 5, wherein the wireless receiver is determined. The noise receiver is
A plurality of integration circuits for integrating the levels of the signals received by the receiving unit at a plurality of different timings, respectively;
The radio reception apparatus according to claim 1, wherein the integration values in the plurality of integration circuits are output to the noise floor value generation unit as levels of the plurality of signals. The noise floor value generation unit
The noise floor value is newly generated as a second noise floor value,
When the second noise floor value exceeds a preset predetermined range, the noise floor value is newly generated as a second noise floor value again,
The radio reception apparatus according to claim 1, wherein when the second noise floor value is within the range, the second noise floor value is output as the first noise floor value.

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