WO2014199600A1 - Wireless receiving device and wireless receiving method - Google Patents

Abstract

This wireless receiving device is provided with a receiving means which generates a digital signal on the basis of a received signal, and a receiving method setting means which measures the signal quality of the digital signal generated on the basis of the received signal and generates a measured signal quality, selects a receiving method of the received signal by comparing a preset reference signal quality and the measured signal quality and generates a method selection signal, and, when the signal quality changes, generates and outputs a control signal depending on the method selection signal, wherein the receiving method is switched to a method in which power consumption changes depending on the control signal. This wireless receiving device can be adapted to multiple wireless methods, switches the receiving method depending on the reception environment, and can operate with low power consumption while securing reception performance.

Description

Radio receiving apparatus and radio receiving method

The present invention relates to a wireless reception apparatus and a wireless reception method capable of switching reception methods according to received signal quality.

The superheterodyne method is widely used as a wireless reception method. In the superheterodyne method, a received radio frequency signal (hereinafter referred to as an RF signal) is once converted into an intermediate frequency signal and then converted into a baseband signal (RF: Radio Frequency).

In the superheterodyne receiver, an external filter for image suppression and channel selection is required in the part that converts the RF signal into an intermediate frequency signal (hereinafter referred to as IF signal) (IF: Intermediate Frequency). Therefore, in the superheterodyne receiver, there are limits to the reduction in the number of parts and the downsizing of the receiver. In addition, it is not easy to change the frequency and bandwidth corresponding to the filters required for image suppression and channel selection. Therefore, the superheterodyne receiver is not suitable for a multi-mode wireless device that supports a plurality of frequency bands.

On the other hand, there is a zero IF method (BB: Baseband) as a method for directly converting a baseband signal (hereinafter referred to as a BB signal) without converting an RF signal into an IF signal. The zero IF method is also called a zero IF method because an IF signal is unnecessary.

The zero IF method eliminates the need for image suppression because there is no IF signal, and an external filter can be deleted. Therefore, the zero IF method has an advantage that the receiver device configuration is simpler than the superheterodyne method. The zero-IF method is highly versatile, can be applied to any wireless method, and is suitable for a multimode wireless device.

However, it is known that with the zero IF method, reception performance is degraded due to the influence of DC offset, flicker noise, and the like (DC: Direct Current).

In addition, there is a system called a low IF system as a system that compensates for the drawbacks of the zero IF system described above. The low IF method is a method in which an RF signal is converted into an IF signal having a frequency slightly higher than that of the BB signal, and the frequency is converted again into baseband by digital processing.

The low IF method requires image suppression processing unlike the zero IF method. However, in the low IF method, since image suppression processing is performed in a digital stage, an external filter can be deleted. For this reason, the low-IF scheme simplifies the apparatus configuration of the receiver, similarly to the zero-IF scheme. In addition, the low IF method is highly versatile like the zero IF method, and can be applied to any wireless method.

The low IF method is less susceptible to the effects of DC offset and flicker noise that cause the reception performance of the zero IF method to deteriorate, so the reception performance is better than the zero IF method. However, the output of the quadrature demodulation unit needs to acquire a wideband signal instead of the baseband, and the sampling frequency of the AD conversion unit is set high, so that there is a disadvantage that the power consumption becomes high (AD: Analog- Digital). Patent Document 1 proposes a receiver configuration that can switch a reception method to both a zero IF method and a low IF method, and a method of using the receiver. Patent Document 1 is characterized in that it is configured to be switched to one of two systems, a zero IF system and a low IF system, in accordance with a wireless standard to be received.

On the other hand, Patent Document 2 proposes a technique for reducing the power consumption of the receiver. Although the receiver of Patent Document 2 is not configured to switch between the zero IF method and the low IF method, it detects the received signal power and the contents (packets) of the received signal and controls the circuit operation. This is characterized by low power consumption.

Patent Document 3 discloses a wireless receiver that can be operated in a zero IF mode and a low IF mode. According to the wireless receiver disclosed in Patent Document 3, it is possible to select an appropriate reception method according to the wireless standard.

Also, Patent Document 4 discloses a receiving apparatus that can realize good reception characteristics and power saving in a plurality of modulation schemes. According to the receiving device of Patent Document 4, it is possible to change the gain of the amplifier when the modulation method is switched.

JP 2006-121160 A Japanese Patent No. 4506343 Special table 2004-515104 gazette JP 2003-204364 A

The receiver of Patent Document 1 is configured to switch to either the zero IF method or the low IF method according to the wireless standard. However, since the receiver of Patent Document 1 does not recognize the reception environment (received signal quality), there is a problem that power consumption cannot be automatically suppressed.

Further, the receiver of Patent Document 2 has a zero IF system configuration, so that power consumption can be reduced, but there is a problem that reception performance may not be secured when reception power is weak.

In addition, the wireless receiver of Patent Document 3 has a problem that it can not switch the reception method according to the change of the reception environment, while it can switch the reception method when switching the wireless standard to be received. there were.

Further, the receiving device of Patent Document 4 has a problem that it can change the gain of the amplifier when the modulation method is switched, but cannot change the receiving method according to the change in the reception environment.

An object of the present invention is applicable to a plurality of radio systems, and switches between reception systems according to the reception environment, and a radio reception apparatus and radio reception method capable of operating with low power consumption while ensuring reception performance Is to provide.

The wireless receiver of the present invention includes a receiving means for generating a digital signal based on a received signal, a signal quality of the digital signal generated based on the received signal to generate a measurement signal quality, and a generated measurement signal Based on the comparison result between the quality and the preset reference signal quality, a reception signal reception method is selected to generate a method selection signal, and when the signal quality changes, a control signal is generated according to the method selection signal. Receiving means setting means for outputting the generated control signal to the receiving means, and switching the receiving method to a method with different power consumption according to the control signal.

In the wireless reception method of the present invention, a digital signal is generated based on the received signal, a signal quality of the digital signal generated based on the received signal is measured to generate a measurement signal quality, and the generated measurement signal quality and Based on the comparison result with the preset reference signal quality, the reception signal reception method is selected to generate a method selection signal, and when the signal quality changes, a control signal is generated according to the method selection signal, and control is performed. The reception method is switched to a method with different power consumption according to the signal.

According to the present invention, a radio receiving apparatus and a radio receiving method that can be applied to a plurality of radio systems, and that can switch the reception system according to the reception environment and operate with low power consumption while ensuring reception performance. Can be provided.

It is the block diagram which showed the structure of the radio | wireless receiver which concerns on the outline | summary of embodiment of this invention. It is the block diagram which showed the structure of the radio | wireless receiver which concerns on the outline | summary of embodiment of this invention in detail. It is the figure which showed the structure of the zero IF receiver based on the outline | summary of embodiment of this invention. It is the figure which showed the structure of the low IF receiver which concerns on the outline | summary of embodiment of this invention. It is a figure which shows the structure of the radio | wireless receiver which concerns on the 1st Embodiment of this invention. 3 is a flowchart illustrating an operation of the wireless reception device according to the first embodiment of the present invention. It is a figure which shows the structure of the radio | wireless receiver which concerns on the 2nd Embodiment of this invention. It is a figure which shows the structure of the radio | wireless receiver which concerns on the 3rd Embodiment of this invention. 7 is a flowchart illustrating an operation of a wireless reception device according to a third embodiment of the present invention. It is a figure which shows the structure of the radio | wireless receiver which concerns on the 4th Embodiment of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the preferred embodiments described below are technically preferable for carrying out the present invention, but the scope of the invention is not limited to the following.

(Overview)
First, the radio reception apparatus 1 according to the outline of the embodiment of the present invention will be described with reference to FIG. The wireless reception device 1 according to the outline of the embodiment of the present invention includes a reception method setting unit 2 and a reception unit 3.

The receiving means 3 receives an RF signal (received signal) and converts the received signal into a digital signal (RF: Radio Frequency). The reception method setting means 2 measures the signal quality of the digital signal converted by the reception means 3 to generate a measurement signal quality, and receives the received signal based on a comparison result between the generated measurement signal and a preset reference signal quality. A reception method is selected to generate a method selection signal. Then, the reception method setting unit 2 generates a control signal according to the method selection signal when the signal quality changes, and outputs the generated control signal to the reception unit 3. The reception unit 3 switches the reception method to a method with different power consumption according to the input control signal.

The radio reception apparatus 1 according to the outline of the embodiment of the present invention is characterized in that, when the signal reception environment (signal quality) changes, the radio reception apparatus 1 switches to a reception method with different power consumption. Therefore, it is possible to secure reception characteristics and reduce power consumption. In the embodiment of the present invention, switching between the zero IF method and the low IF method will be described. However, the scope of the present invention is not limited to switching between the zero-IF method and the low-IF method, but wireless that can switch to a receiving method with different power consumption when the signal reception environment (signal quality) changes. Includes communication methods.

As signal quality, for example, a signal-to-noise power ratio (SNR) can be used as an index (SNR: Signal to Noise Ratio). Note that in the wireless reception device 1 according to the outline of the embodiment of the present invention, the signal quality of a signal may be used as an index. Therefore, an index that is not a signal-to-noise power ratio may be used as the signal quality.

Next, detailed configurations of the reception method setting unit 2 and the reception unit 3 of the wireless reception device 1 according to the outline of the embodiment of the present invention will be described with reference to FIG.

The reception means 3 includes a high-frequency unit 11, an orthogonal demodulation unit 12, a low-pass filter unit 13, an AD conversion unit 14, a frequency conversion unit 15, a reception system switching unit 16, a rate conversion unit 17, a demodulation / decoding unit And a processing unit 18.

The high frequency unit 11 which is a high frequency means receives an RF signal, attenuates a signal other than the reception frequency band, amplifies the desired band signal, and outputs a desired RF signal. The desired band signal is an RF signal to be received in the reception frequency band.

The quadrature demodulating unit 12 serving as a quadrature demodulating unit receives the output of the high frequency unit 11 and mixes the output of the high frequency unit 11 and a pair of orthogonal local oscillation signals based on the frequency / gain setting of the local oscillator. The quadrature demodulator 12 then outputs IF and baseband I and Q signals (first analog baseband signals).

The low-pass filter unit 13 which is a low-pass filter means band-limits the I and Q signals output from the quadrature demodulator 12 based on the pass band setting, and the intermediate frequency (IF) or baseband I and Q signals (second Analog baseband signal).

The AD conversion unit 14 serving as an analog-digital conversion unit converts the I and Q signals output from the low-pass filter unit 13 from analog signals to digital signals, and outputs IF frequency or baseband I and Q signals (first digital base). Band signal).

The frequency conversion unit 15, which is a frequency conversion means, receives the I and Q signals output from the AD conversion unit 14 and inputs the I and Q signals output from the AD conversion unit 14, the numerical control oscillator, and the shift based on the numerical control oscillator setting. Frequency conversion is performed by complex multiplication of the complex signal output from the phase shifter. Hereinafter, the numerically controlled oscillator is abbreviated as NCO (NCO: Numerically Controlled Oscillator). The frequency converter 15 then outputs baseband I and Q signals (second digital baseband signals).

The reception method switching unit 16 serving as a reception method switching unit switches whether to output the second digital baseband signal output from the frequency conversion unit 15 to the rate conversion unit 17. That is, the reception method switching unit 16 switches the reception method to either the zero IF method or the low IF method.

When the second digital baseband signal is output from the frequency conversion unit 15 to the rate conversion unit 17 by switching the reception method switching unit 16, the low IF method is selected.

In addition, when the second digital baseband signal is not output to the rate conversion unit 17 by switching the reception method switching unit 16, the zero IF method is selected. Note that the case where the second digital baseband signal is not output to the rate conversion unit 17 means that the first digital baseband signal output from the AD conversion unit 14 is converted into the second digital baseband signal by the frequency conversion unit 15. It means outputting to the rate conversion unit 17 without conversion.

The reception method switching unit 16 is inserted either between the frequency conversion unit 15 and the rate conversion unit 17 or between the AD conversion unit 14 and the frequency conversion unit 15.

When the reception method switching unit 16 is inserted between the frequency conversion unit 15 and the rate conversion unit 17, the first digital baseband signal is output to both the frequency conversion unit 15 and the reception method switching unit 16. . In FIG. 2, the AD converter 14, the frequency converter 15, the reception method switching unit 16, and the rate conversion unit 17 in the order of the route (the one-dot chain line), the AD conversion unit 14, the reception method switching unit 16, and the rate conversion unit 17. A signal propagates through two routes, a sequential route (solid line and one-dot chain line). The reception method switching unit 16 outputs either the first digital baseband signal or the second digital baseband signal to the rate conversion unit 17 based on the input selection setting (setting I: one-dot chain line) of the functional block setting unit 21. In this case, for example, a signal switching unit including a multiplexer or the like can be used as the reception method switching unit 16.

When the reception method switching unit 16 is inserted between the AD conversion unit 14 and the frequency conversion unit 15, the first digital baseband signal is output to the reception method switching unit 16. In FIG. 2, the signal propagates through an order route (solid line and two-dot chain line) of the AD conversion unit 14, the reception method switching unit 16, the frequency conversion unit 15, and the rate conversion unit 17. The reception method switching unit 16 converts the first digital baseband signal and outputs it to the frequency conversion unit 15. Note that the reception method switching unit 16 also includes outputting the first digital baseband signal without change in the above-described conversion. In this case, for example, a signal correction unit such as a signal correction unit can be used as the reception method switching unit 16.

The rate conversion unit 17 serving as a rate conversion unit, via the reception method switching unit 16, outputs the AD conversion unit 14 (first digital baseband signal) or the output of the frequency conversion unit 15 (second digital baseband signal). ) As an input, and based on the rate conversion rate setting, the sampling rate of the input signal is reduced and output as a third digital baseband signal. Note that a method for selecting an input signal to the rate conversion unit 17 will be specifically described in the description of the multiplexer unit and the signal correction unit described in the first to fourth embodiments.

The demodulation / decoding processing unit 18 which is a demodulation / decoding processing means receives the output of the rate conversion unit 17 and performs demodulation / decoding processing corresponding to the wireless standard. When the bit error rate (BER) characteristic is used for reception quality evaluation, the demodulation / decoding processing unit 18 outputs the bit error rate (BER) measured from the processing result to the reception method selection unit 20 as the measurement BER. (BER: Bit Error Rate).

The reception method setting means 2 includes a signal quality measurement unit 19, a reception method selection unit 20, and a functional block setting unit 21.

The signal quality measuring unit 19 serving as a signal quality measuring unit receives the I and Q signals output from the AD converting unit 14 as input, measures the signal quality from the input signal, and outputs the measured signal quality.

The reception method selection unit 20 serving as a reception method selection unit receives the measurement signal quality output from the signal quality measurement unit 19 and compares the measurement signal quality with a preset reference signal quality to select a reception method. And output as a method selection signal. That is, the reception method selection unit 20 selects either the zero IF method or the low IF method as the reception method. For example, when the measurement signal quality is higher than the reference signal quality, the zero IF method is selected, and when the measurement signal quality is lower than the reference signal quality, the low IF method is selected. However, when the measurement signal quality is the same quality as the reference signal quality, any method may be selected, but it is preferable to select the zero IF method that achieves low power consumption.

A functional block setting unit 21 serving as a functional block setting unit receives a method selection signal output from the reception method selection unit 20 as an input, and receives an orthogonal demodulation unit 12, a low-pass filter unit 13, an AD conversion unit 14, a frequency conversion unit 15, and a reception method switching. Control signals for controlling the operation states of the unit 16 and the rate conversion unit 17 are output.

The functional block setting unit 21 sets the local oscillator frequency / gain setting (setting LG) in the quadrature demodulation unit 12, sets the passband (setting B) in the low-pass filter unit 13, and sets the sampling frequency (settings) in the AD conversion unit 14. The control signal regarding S) is output. Further, the function block setting unit 21 sets the NCO frequency setting (setting N) in the frequency conversion unit 15, the input selection setting (setting I) in the reception method switching unit 16, and the rate conversion rate setting (setting in the rate conversion unit 17). A control signal for R) is output.

When the operation of the frequency conversion unit 15 that is not used in the zero IF method is stopped by clock gating control, the functional block setting unit 21 controls the frequency conversion unit 15 to control signals related to clock gating control setting (setting C). May be output. When the reception method switching unit 16 calculates the correction parameter and corrects the signal, the functional block setting unit 21 does not need to output a control signal to the reception method switching unit 16.

With the configuration as described above, the wireless reception device 10 according to the present embodiment selects one of the reception methods of the zero IF method and the low IF method according to the received signal quality, and each function of the wireless reception device 10 Change the reception method by changing the block setting. In the present embodiment, each functional block refers to each of the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 15, the reception method switching unit 16, and the rate conversion unit 17. A group of functional blocks including the orthogonal demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 15, the reception method switching unit 16, and the rate conversion unit 17 is referred to as a functional block group.

Next, a reception method switched by the wireless reception device 1 will be described. The wireless reception device 1 according to the outline of the embodiment of the present invention switches the reception method to either the zero IF method or the low IF method.

(Zero IF method)
FIG. 3 is a diagram showing a configuration of the zero IF receiver 5 according to the embodiment of the present invention. The zero IF receiver 5 corresponds to the case where the frequency conversion unit 15 is not used in the wireless reception device 1.

The zero IF receiver 5 includes a high-frequency unit 11, an orthogonal demodulation unit 12, a low-pass filter unit 13, an AD conversion unit 14, a rate conversion unit 17, and a demodulation / decoding processing unit 18. The internal configuration of each component will be described in detail in the first to fourth embodiments.

The high frequency unit 11 includes a band pass filter 111, a low noise amplifier 112, and a low pass filter 113.

The quadrature demodulator 12 includes a local oscillator 121, a phase shifter 122, a pair of mixers 123 and 124, and a pair of amplifiers 125 and 126.

The low pass filter unit 13 includes a pair of low pass filters 131 and 132.

The AD converter 14 includes a pair of ADCs (Analog / Digital Converters) 141 and 142 (Analog to Digital Converter).

The rate conversion unit 17 includes a pair of rate converters 171 and 172.

Here, the operation of the zero IF receiver 5 will be briefly described.

When an RF signal is input to the zero IF receiver 5, the high frequency unit 11 attenuates a signal outside the reception frequency band and amplifies the signal.

Next, the quadrature demodulator 12 mixes the output signal of the local oscillator that outputs a local oscillation signal having a frequency substantially the same as the reception frequency, the signal obtained by shifting the local oscillation signal by 90 degrees, and the amplified signal. . In this way, baseband I signals (in-phase components) and Q signals (quadrature components) that are in a quadrature relationship are generated.

Next, after the unnecessary wave is removed by band-limiting the I and Q signals in the low-pass filter unit 13, the analog signal is converted into a digital signal in the AD conversion unit 14.

Then, the demodulation / decoding processing unit 18 down-samples the I and Q signals converted into digital signals by the rate conversion unit 17 to a desired sampling rate, and performs carrier demodulation and error correction processing.

The above is the description of the operation of the zero IF receiver 5. Note that the low-IF receiver 100 shown in FIG. 3 is an example of a low-IF receiver, and is not necessarily the same as the configuration shown in FIG. 3 as long as it can receive an RF signal using the low-IF method. It does not have to be.

(Low IF method)
FIG. 4 is a configuration diagram showing an example of the low IF method. The low IF receiver 6 will be described with reference to FIG. The low IF receiver 6 corresponds to the case where the frequency conversion unit 15 is used in the wireless reception device 1.

However, components having the same functions as those in FIG. 3 are given the same names and numbers, and detailed descriptions thereof are omitted. The internal configuration of each component will be described in detail in the first to fourth embodiments.

The low IF receiver 6 includes a frequency converter 15 between the AD converter 14 and the rate converter 17 in addition to the configuration of the zero IF receiver 5 shown in FIG.

The frequency converter 15 includes an NCO 151, a phase shifter 152, four multipliers 153 to 156, and a pair of adders 157 and 158.

Here, the operation of the low IF receiver 6 will be briefly described.

When an RF signal is input to the low IF receiver 6, the high frequency unit 11 attenuates a signal other than the reception frequency band and amplifies the signal in the reception frequency band.

Next, the quadrature demodulator 12 mixes an output signal of a local oscillator that outputs a local oscillation signal having a frequency slightly lower than the reception frequency, a signal obtained by shifting the local oscillation signal by 90 degrees, and an amplified signal. . In this way, an I signal (in-phase component) and a Q signal (quadrature component) of an intermediate frequency (IF) having a quadrature relationship are generated.

Next, after removing unnecessary waves by band-limiting the I and Q signals with the low-pass filter unit 13, the analog signal is converted into a digital signal with the AD conversion unit 14.

Next, the frequency conversion unit 15 performs frequency conversion again, and converts the signals into baseband I and Q signals that are orthogonal to each other.

Further, the rate conversion unit 17 downconverts the I and Q signals to a desired sampling rate, and the demodulation / decoding processing unit 18 performs carrier demodulation and error correction processing.

The above is the description of the operation of the low IF receiver 6. The low IF receiver 6 shown in FIG. 4 is an example of a low IF receiver, and is not necessarily the same as the configuration shown in FIG. 4 as long as it can receive an RF signal by the low IF method. It does not have to be.

According to the wireless reception device 1 according to the outline of the embodiment of the present invention, as described above, when the signal reception environment (signal quality) is changed, the zero IF method and the low IF method are switched, so that reception characteristics are ensured. In addition, power consumption can be reduced. Further, the radio reception method according to the outline of the embodiment of the present invention can be applied not only to switching between the zero IF method and the low IF method, but also to a radio reception method capable of switching to a reception method with different power consumption. .

Subsequently, details of the operation of the wireless reception device 1 according to the present embodiment will be described using the wireless reception devices 10 to 40 according to the following first to fourth embodiments.

(First embodiment)
FIG. 5 shows an example of a block configuration diagram of the wireless reception device 10 according to the first embodiment of the present invention.

In FIG. 5, the radio receiving apparatus 10 according to the present embodiment includes a high frequency unit 11, an orthogonal demodulation unit 12, a low pass filter unit 13, an AD conversion unit 14, a frequency conversion unit 15, a multiplexer unit 160, a rate A conversion unit 17 and a demodulation / decoding processing unit 18 are provided.

Furthermore, the wireless reception device 10 according to the present embodiment includes a signal quality measurement unit 19, a reception method selection unit 20, and a functional block setting unit 21.

Since the configuration other than the multiplexer unit 160 is as described in the description of the outline of the above-described embodiment, the description thereof is omitted.

The multiplexer unit 160 has a function of switching between the zero IF method and the low IF method.

The multiplexer unit 160 includes a pair of multiplexers 161 and 162. The multiplexer unit 160 receives the output of the AD conversion unit 14 and the output signal of the frequency conversion unit 15 as inputs, and selects and outputs one of the input signals based on the input selection setting from the functional block setting unit 21.

The functional block setting unit 21 receives a method selection signal output from the reception method selection unit 20 as an input. Based on the input method selection signal, the functional block setting unit 21 determines the operation states of the orthogonal demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 15, the multiplexer unit 160, and the rate conversion unit 17, respectively. A control signal to be controlled is output.

The functional block setting unit 21 sets the local oscillator frequency / gain setting (setting LG) in the quadrature demodulation unit 12, sets the passband (setting B) in the low-pass filter unit 13, and sets the sampling frequency (settings) in the AD conversion unit 14. The control signal regarding S) is output. Further, the function block setting unit 21 has an NCO frequency setting (setting N) in the frequency converting unit 15, an input selection setting (setting I) in the multiplexer 160, and a rate conversion rate setting (setting R) in the rate converting unit 17. The control signal for is output.

With the configuration as described above, the wireless reception device 10 according to the present embodiment selects one of the reception methods of the zero IF method and the low IF method according to the received signal quality, and each function of the wireless reception device 10 Change the reception method by changing the block setting. In the present embodiment, each functional block refers to the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 15, the multiplexer unit 160, and the rate conversion unit 17.

Here, the setting of each functional block accompanying the selection of the reception method of the wireless reception device 10 in the reception method selection unit 20 will be described.

When the zero IF method is selected as the reception method of the wireless receiver 10, the output of the quadrature demodulator 12 is set by setting the frequency of the local oscillator 121 to substantially the same frequency as the frequency of the input RF signal. The I and Q signals are baseband signals. At this time, since the output of the AD conversion unit 14 is already baseband, the frequency conversion is not performed by the frequency conversion unit 15. Further, the multiplexer unit 160 selects the input on the output side of the AD conversion unit 14.

On the other hand, when the low IF method is selected as the reception method of the wireless reception device 10, the frequency of the local oscillator 121 is set to a frequency slightly lower than the frequency of the input RF signal, so that the orthogonal demodulation unit 12 The output I and Q signals are low IF signals. At this time, since the output of the AD conversion unit 14 is a low IF, the frequency conversion unit 15 performs frequency conversion to convert it into a baseband signal. Further, the multiplexer unit 160 selects the input on the output side of the frequency conversion unit 15.

In the low-pass filter unit 13, an appropriate pass band is set for each reception method.

When the zero IF method is selected, the AD conversion unit 14 sets a lower sampling rate suitable for the baseband signal. When the low IF method is selected, the AD conversion unit 14 sets a higher sampling rate suitable for the low IF signal. However, the level of the sampling rate means a relative level when comparing the sampling rates suitable for the zero IF method and the low IF method.

Then, in the rate conversion unit 17, when the zero IF method is selected, the conversion rate is set small, and when the low IF method is selected, the conversion rate is set large. Note that setting the conversion rate to a small value means that the rate is not reduced so much. Setting a large conversion rate means that the rate is greatly reduced. However, the rate decrease / decrease is determined relatively between the respective methods when the reception method is switched between the zero IF method and the low IF method.

(Operation)
FIG. 6 is a flowchart showing an example of processing of the wireless reception device 10 according to the first embodiment of the present invention. Hereinafter, the operation of the wireless reception device 10 according to the present embodiment will be described with reference to FIG. In the flowchart of FIG. 6, the operation of each functional block is omitted.

First, the wireless receiver 10 is initially set by a host controller or the like (step S1). Here, it is assumed that reception is started by the zero IF method in order to reduce power consumption.

In the initial setting in step S1, the radio frequency unit 11, the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 correspond to radio standards received and are suitable for operating in the zero IF system. Settings are made. In the multiplexer unit 160, the output of the AD conversion unit 14 is selected.

When the initial setting for the wireless receiving device 10 is completed, an RF signal input is started from the outside, and the wireless reception process is started. As described above, in this description, reception by the zero IF method is started.

The high frequency unit 11 attenuates the signal outside the reception frequency band set in step S1 and amplifies the signal with respect to the input RF signal, and outputs a desired RF signal.

Next, in the orthogonal demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S1. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of baseband I and Q signals. Is output. Also, the amplifiers 125 and 126 amplify the pair of baseband I and Q signals and output them as the first analog baseband signals to the outside.

Next, in the low-pass filter unit 13, the pair of low- pass filters 131 and 132 allows the input first analog baseband signal to pass through the passband set in step S <b> 1, and the second analog baseband. Output to the outside as a signal.

Next, in the AD converter 14, the pair of AD converters 141 and 142 digitally convert the input second analog baseband signal at the sampling rate set in step S1. The AD converter 14 then outputs the digitally converted signal to the outside as a first digital baseband signal.

Next, in the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input (first digital baseband signal) on the AD conversion unit 14 side set in step S1, and outputs the selected signal to the outside. .

Next, in the rate conversion unit 17, the pair of rate converters 171 and 172 convert the rate of the first digital baseband signal input at the rate conversion rate set in step S1, and convert the converted signal to the first 3 as a digital baseband signal.

Next, the demodulation / decoding processing unit 18 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal.

Here, the signal quality measurement unit 19 measures a signal-to-noise power ratio (SNR: Signal to Noise Ratio) as the signal quality of the received signal from the first digital baseband signal output from the AD conversion unit 14. Then, the signal quality measuring unit 19 outputs the measured signal-to-noise power ratio as measured signal quality (measured SNR value) (step S2).

In the following, first, a case where the measurement signal quality is lower than the reference signal quality (in the case of Yes in step S3) will be described. At this stage, reception is performed by the zero IF method as described above.

The reception method selection unit 20 compares the measurement signal quality (measurement SNR value) output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is lower than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the low IF method (step S4).

When a method selection signal for selecting the low IF method output from the reception method selection unit 20 is input, the functional block setting unit 21 is currently in the zero IF method, and therefore sets the low IF method for each functional block. It is decided to perform (step S5).

Here, if it is the low IF method, the current loop is terminated without changing the method.

Next, a setting signal for setting each functional block to the low IF method is generated, and the setting signal is output to each functional block (step S6).

Thus, appropriate settings for operating in the low IF method are performed in accordance with the wireless standards received by the high frequency unit 11, the quadrature demodulation unit 12, the low pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17.

Here, the wireless reception device 10 starts the operation in the low IF method and ends the current loop.

Next, the case where the measurement signal quality is higher than the reference signal quality (No in step S3) will be described. Here, it continues to receive an RF signal input from the outside and performs wireless reception processing. As described above, reception is performed at this stage using the low IF method.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S6. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal phase-shifted 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of intermediate frequency (IF) I's. , Q signal is output. In addition, the amplifiers 125 and 126 amplify the above-described pair of intermediate frequency (IF) I and Q signals and output the amplified signals to the outside as a first analog baseband signal. A signal obtained by amplifying the I and Q signals is also an intermediate frequency (IF) signal, but is referred to as a baseband signal in order to have the same name as the above signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S 6 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 performs analog / digital conversion on the input second analog baseband signal at the sampling rate set in step S <b> 6, and performs the first digital conversion. Output to the outside as a baseband signal.

In the frequency converter 15, the NCO 151 outputs a numerically controlled oscillation signal having the frequency set in step S6. Multipliers 153 and 156 multiply the output of NCO 151 and the first digital baseband signal. Multipliers 154 and 155 multiply the NCO 151 output by the phase shift numerically controlled oscillation signal whose phase is shifted by 90 degrees by the phase shifter 152 and the first digital baseband signal. The adders 157 and 158 add and subtract the two pairs of signals output from the multipliers 153 to 156, and output the resulting signal as a second digital baseband signal.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input on the frequency conversion unit 15 side set in step S6, that is, the second digital baseband signal, and outputs it to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 converts the rate of the second digital baseband signal input at the rate conversion rate set in step S6, and forms a third digital baseband signal. Output to the outside.

The demodulation / decoding processing unit 18 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal.

As described above, the signal quality measurement unit 19 measures the SNR of the received signal from the first digital baseband signal that is the output of the AD conversion unit 14, and outputs the measured SNR as a measured SNR value (step S2). .

The reception method selection unit 20 compares the measured SNR value that is the output of the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is higher than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the zero IF method (step S7).

When a method selection signal for selecting the zero IF method output from the reception method selection unit 20 is input, the functional block setting unit 21 is currently in the low IF method, and therefore sets the zero IF method for each functional block. It is decided to perform (step S8).

Next, the functional block setting unit 21 generates a setting signal for setting each functional block to the low IF method, and outputs the setting signal to each functional block (step S9).

Thereby, the wireless reception device 10 starts operation in the zero IF method.

Then, the same operation is continued, and the loop is exited when wireless reception is completed.

As described above, when the signal quality is poor (SNR is low), the zero IF method, in which the reception performance may be deteriorated, is changed to the low IF method in which the reception performance can be improved with respect to the zero IF method. On the other hand, when the signal quality is good (SNR is high), the low IF method with high power consumption is changed to the zero IF method that can reduce power consumption with respect to the low IF method.

As described above, according to the wireless reception device 10 according to the first embodiment of the present invention, the power consumption is maintained while maintaining the reception performance to some extent by changing the reception method based on the measured signal quality. Can be reduced.

(Second Embodiment)
Next, a radio reception apparatus 200 according to the second embodiment of the present invention will be described. In the second embodiment, a clock gating control input is added to the frequency conversion unit 31 of the first embodiment.

FIG. 7 shows an example of a block configuration diagram of the receiving apparatus according to the present embodiment.

In FIG. 7, the radio reception device 200 according to the second embodiment of the present invention has been changed so that clock gating control is input to the frequency conversion unit 15 of the first embodiment in addition to the NCO setting. Is. Further, the function block setting unit 21 is changed so that clock gating control is output in addition to the NCO setting.

In the second embodiment, since the operation of the frequency converter 31 that is not used in the zero IF method is stopped by clock gating control, the power consumption of the zero IF method is reduced.

Hereinafter, the wireless reception device 200 according to the second embodiment will be described in more detail. In FIG. 7, the configuration of the parts not shown above is the same as that of the receiving apparatus 10 according to the first embodiment. Therefore, the same elements are denoted by the same names and reference numerals, and detailed description thereof will be omitted. Omitted.

The frequency conversion unit 31 includes an NCO (Numerically Controlled Oscillator) 151, a phase shifter 152, four multipliers 153 to 156, and a pair of adders 157 and 158. The frequency conversion unit 31 receives the I and Q signals output from the AD conversion unit 14 as inputs and performs complex multiplication of the output of the AD conversion unit 14 and the complex signals output from the NCO 151 and the phase shifter 152 based on the NCO setting. Perform frequency conversion with. The frequency converter 31 then outputs baseband I and Q signals (second digital baseband signals). Further, the frequency conversion unit 31 stops the operation based on the clock gating setting by the functional block setting unit 26.

The functional block setting unit 26 receives the method selection signal output from the reception method selection unit 20 as an input, and receives the orthogonal demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 31, the multiplexer unit 160, and the rate conversion unit 17. A control signal for controlling each operation state is output.

The functional block setting unit 26 sets the local oscillator frequency / gain setting (setting LG) in the quadrature demodulation unit 12, sets the passband (setting B) in the low-pass filter unit 13, and sets the sampling frequency (settings) in the AD conversion unit 14. The control signal regarding S) is output. The function block setting unit 21 includes an NCO frequency setting (setting N) and a clock gating control setting (setting C) in the frequency conversion unit 15, an input selection setting (setting I) in the multiplexer unit 160, and a rate conversion unit 17. Outputs a control signal related to rate conversion rate setting (setting R).

Except for the frequency conversion unit 31 and the functional block setting unit 26 described above, the second embodiment is the same as the first embodiment shown in FIG.

(Operation)
The operation of the wireless reception device 200 according to the second embodiment of the present invention will be described with reference to FIGS. Here, similarly to the description of the operation of the first embodiment, the description will be given in order for the case where the low IF method is selected and the case where the zero IF method is selected.

First, the wireless receiver 200 is initially set by a host controller or the like (step S1). Here, it is assumed that reception is started by the zero IF method in order to reduce power consumption. The operations of the following functional blocks are not shown in the flowchart of FIG.

In the initial setting in step S1, the radio frequency unit 11, the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 correspond to radio standards received and are suitable for operating in the zero IF system. Settings are made. The multiplexer unit 160 selects an input on the output side of the AD conversion unit 14. Further, the frequency converter 31 stops its operation because the clock supply is stopped by the clock gating control.

When the initial setting for the wireless receiving device 10 is completed, an RF signal input is started from the outside, and the wireless reception process is started. As described above, reception by the zero IF method is started here.

The high frequency unit 11 attenuates the signal outside the reception frequency band set in step S1 and amplifies the signal with respect to the input RF signal, and outputs a desired RF signal.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S1. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and generate a pair of baseband I and Q signals. Output. In addition, the amplifiers 125 and 126 amplify the pair of baseband I and Q signals described above and output the amplified signals to the outside as the first analog baseband signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S1 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 digitally convert the input second analog baseband signal at the sampling rate set in step S1. Then, the AD conversion unit 14 outputs a signal obtained by digitally converting the second analog baseband signal to the outside as the first digital baseband signal.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input (first digital baseband signal) on the AD conversion unit 14 side set in step S1, and outputs the selected signal to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 convert the rate of the first digital baseband signal input at the rate conversion rate set in step S1, and convert the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 18 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal.

Here, the signal quality measurement unit 19 measures the signal-to-noise power ratio (SNR) as the signal quality of the received signal from the first digital baseband signal output from the AD conversion unit 14. Then, the signal quality measuring unit 19 outputs the measured signal-to-noise power ratio as measured signal quality (measured SNR value) (step S2).

In the following, first, a case where the measurement signal quality is lower than the reference signal quality (in the case of Yes in step S3) will be described. At this stage, reception is performed by the zero IF method as described above.

The reception method selection unit 20 compares the measurement signal quality (measurement SNR value) output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is lower than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the low IF method (step S4).

When the function block setting unit 26 receives a method selection signal for selecting the low IF method output from the reception method selecting unit 20, the function block setting unit 26 sets the low IF method for each functional block because it is currently the zero IF method. Is determined (step S5).

Here, if it is the low IF method, the current loop is terminated without changing the method.

Next, a setting signal for setting each functional block to the low IF method is generated, and the setting signal is output to each functional block (step S6). At this time, the functional block setting unit 26 outputs a clock gating control signal to supply a clock to the frequency conversion unit 31.

By the processing in step S6, appropriate settings for operating in the low IF system corresponding to the radio standards received by the high frequency unit 11, the quadrature demodulation unit 12, the low pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 are set. Done. When the setting is made for each functional block, the wireless reception device 200 starts the operation in the low IF method and ends the current loop. At this time, the frequency converter 31 restarts the clock supply by the clock gating control and starts the operation.

Next, a case where the measurement signal quality is higher than the reference signal quality will be described (No in step S3). Continue to receive an RF signal from the outside and perform wireless reception processing. As described above, reception is performed at this stage using the low IF method.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S6. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal phase-shifted 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of intermediate frequency (IF) I's. , Q signal is output. In addition, the amplifiers 125 and 126 amplify the above-described pair of intermediate frequency (IF) I and Q signals and output the amplified signals to the outside as a first analog baseband signal. A signal obtained by amplifying the I and Q signals is also an intermediate frequency (IF) signal, but is referred to as a baseband signal in order to have the same name as the above signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S 6 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 performs analog / digital conversion on the input second analog baseband signal at the sampling rate set in step S <b> 6. Output to the outside as a band signal.

In the frequency conversion unit 31, the NCO 151 outputs a numerically controlled oscillation signal having the frequency set in step S6. Multipliers 153 and 156 multiply the output of NCO 151 and the first digital baseband signal. Further, the multipliers 154 and 155 multiply the phase shift numerical control oscillation signal obtained by shifting the output of the NCO 151 by 90 degrees by the phase shifter 152 and the first digital baseband signal. Adders 157 and 158 respectively add and subtract two pairs of signals output from multipliers 153 to 156, and output the added and subtracted signals to the outside as second digital baseband signals.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the output of the frequency conversion unit 15 set in step S6, that is, the second digital baseband signal, and outputs the selected signal to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 converts the rate of the second digital baseband signal input at the rate conversion rate set in step S6, and converts the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 18 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal.

As described above, the signal quality measurement unit 19 measures the SNR of the received signal from the first digital baseband signal that is the output of the AD conversion unit 14, and outputs the measured SNR as a measured SNR value (step S2). .

The reception method selection unit 20 compares the measured SNR value output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is higher than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the zero IF method (step S7).

When a method selection signal for selecting the zero IF method output from the reception method selection unit 20 is input, the functional block setting unit 26 is currently in the low IF method, and therefore sets the zero IF method for each functional block. It is decided to perform (step S8).

Next, a setting signal for setting each functional block to the low IF method is generated, and the setting signal is output to each functional block (step S9). At this time, the frequency converter 31 stops operating due to clock gating control and does not operate.

The wireless reception device 200 starts the operation in the zero IF method by the process of step S9.

Then, the same operation is continued, and the loop is exited when wireless reception is completed.

As described above, when the signal quality is poor (SNR is low), the zero IF method, in which the reception performance may be deteriorated, is changed to the low IF method in which the reception performance can be improved with respect to the zero IF method. On the other hand, when the signal quality is good (SNR is high), the low-IF method with high power consumption is changed to the zero-IF method that can be expected to reduce power consumption with respect to the low-IF method.

As described above, according to the wireless reception device 200 according to the second embodiment of the present invention, the power consumption is maintained while maintaining the reception performance to some extent by changing the reception method based on the measured signal quality. Can be reduced. Further, in the present embodiment, in addition to the effects of the first embodiment, the clock supply can be stopped when the frequency converter 31 is not used, that is, when the zero IF method is selected. The power consumption can be reduced.

(Third embodiment)
Next, a radio reception device 30 according to the third embodiment of the present invention will be described. In the third embodiment, a case where a bit error rate (BER) characteristic is used for reception quality evaluation will be described (BER: Bit Error Rate).

FIG. 8 shows an example of a block configuration diagram of the receiving apparatus according to the present embodiment.

In FIG. 8, in the radio reception device 30 according to the third embodiment of the present invention, the demodulation / decoding processing unit 18 of the first embodiment outputs a measurement BER, and the reception method selection unit 20 inputs a measurement BER signal. It was changed to accept.

Note that digital broadcasting standards such as ISDB-T and DVB-T stipulate that error correction is performed in two stages (ISDB-T: Integrated Services Digital Broadcasting-Terrestrial, DVB-T: Digital Video Broadcasting Restoration-T ). Common receivers that receive these standards often have a function of measuring the bit error rate (BER) from the difference between the first-stage output and second-stage output bits of error correction. In the present embodiment, it is assumed that a wireless standard capable of obtaining a BER from the demodulation / decoding processing result is received as described above.

In the third embodiment, it is expected that the bit error rate (BER) can be used for selection of the reception method, the accuracy of the method selection is improved, and it is not affected by the instantaneous signal quality fluctuation.

Hereinafter, the wireless reception device 30 according to the third embodiment will be described in more detail. In FIG. 8, the configuration of the parts not shown above is the same as that of the radio receiving apparatus 10 according to the first embodiment, and therefore, the same elements are denoted by the same names and reference numerals, and detailed description is given. Omitted.

The demodulation / decoding processing unit 31 receives the output of the rate conversion unit 17 and performs demodulation / decoding processing corresponding to the wireless standard. Further, the bit error rate (BER) is measured from the processing result, and the measurement BER is output.

The reception method selection unit 32 receives the measurement signal quality value output from the signal quality measurement unit 19 and the measurement BER output from the demodulation / decoding processing unit 31 as inputs, and compares the measurement signal quality with a preset reference signal quality. The method is selected based on the comparison between the measurement BER and a preset reference BER, and is output as a method selection signal.

Other than the demodulation / decoding processing unit 31 and the reception method selection unit 32 described above are the same as those in the first embodiment shown in FIG.

(Operation)
The operation of the wireless reception device 30 according to the third embodiment of the present invention will be described with reference to FIGS. Here, similarly to the description of the operation of the first embodiment, the case where the low IF method is selected and the case where the zero IF method is selected will be described in order.

First, the wireless receiver 30 is initialized by a host controller or the like (step S11). Here, it is assumed that reception is started by the zero IF method in order to reduce power consumption.

Appropriate settings for operating in the zero IF system corresponding to the radio standards received by the high frequency unit 11, the quadrature demodulation unit 12, the low pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 by the initial setting in step S1 Is done. The multiplexer unit 160 selects an input on the output side of the AD conversion unit 14.

When the initial setting for the wireless receiving device 10 is completed, an RF signal input is started from the outside, and the wireless reception process is started. As described above, reception by the zero IF method is started here.

The high frequency unit 11 attenuates the signal outside the reception frequency band set in step S11 and amplifies the signal with respect to the input RF signal, and outputs a desired RF signal.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S11. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of baseband I and Q signals. Is output. In addition, the amplifiers 125 and 126 amplify the pair of baseband I and Q signals described above, and output the amplified signals to the outside as a first analog baseband signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S11 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 perform digital conversion on the input second analog baseband signal at the sampling rate set in step S11. The AD converter 14 outputs the digitally converted signal to the outside as a first digital baseband signal.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input (first digital baseband signal) on the AD conversion unit 14 side set in step S11, and outputs the selected signal to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 convert the rate of the first digital baseband signal input at the rate conversion rate set in step S11, and convert the converted signal to the third rate. Output as a digital baseband signal.

The demodulation / decoding processing unit 31 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal, and outputs a measurement BER (step S12).

Here, the signal quality measurement unit 19 measures the signal-to-noise power ratio (SNR) as the signal quality of the received signal from the first digital baseband signal output from the AD conversion unit 14, and the measurement signal quality (measured SNR value). ) (Step S13).

Hereinafter, first, a case where the measurement signal quality is lower than the reference signal quality (in the case of Yes in step S14) and the measurement BER is lower than the reference BER (in the case of Yes in step S15) will be described. At this stage, reception is performed by the zero IF method as described above.

The reception method selection unit 32 compares the measured SNR value output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S11 (step S14). The reception method selection unit 32 compares the measurement BER output from the demodulation / decoding processing unit 31 with the reference BER set in step S11 (step S15), and outputs a method selection signal for selecting the low IF method. (Step S16).

When the method selection signal for selecting the low IF method output from the reception method selection unit 32 is input, the function block setting unit 21 is currently in the zero IF method, and therefore the function block setting unit 21 sets the low IF method for each functional block. Is determined to be performed (step S17).

Here, if it is the low IF method, the current loop is terminated without changing the method.

Next, the functional block setting unit 21 generates a setting signal for setting each functional block to the low IF method, and outputs the setting signal to each functional block (step S18).

By the processing in step S18, an appropriate setting for operating in the low IF system corresponding to the radio standard received by the high-frequency unit 11, the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 is performed. Done. Then, the wireless reception device 30 starts the operation in the low IF method and ends the current loop.

Next, a case where the measurement signal quality is higher than the reference signal quality will be described (No in step S14). Continue to receive an RF signal from the outside and perform wireless reception processing. As described above, reception is performed by the low IF method.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S18. In the quadrature demodulating unit 12, the mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal phase-shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of intermediate frequencies. (IF) I and Q signals are output. The amplifiers 125 and 126 amplify the above-described pair of intermediate frequency (IF) I and Q signals, and output the amplified signals to the outside as first analog baseband signals. A signal obtained by amplifying the I and Q signals is also an intermediate frequency (IF) signal, but is referred to as a baseband signal in order to have the same name as the above signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S18 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 performs analog conversion on the input second analog baseband signal at the sampling rate set in step S18. The AD converter 14 outputs the digitally converted signal to the outside as a first digital baseband signal.

In the frequency converter 15, the NCO 151 outputs a numerically controlled oscillation signal having the frequency set in step S18. Multipliers 153 to 156 multiply the output of the NCO 151 and the phase-shifted numerically controlled oscillation signal shifted by 90 degrees by the phase shifter 152 and the first digital baseband signal. Adders 157 and 158 add / subtract the two pairs of signals output from multipliers 153 to 156, and output the added / subtracted signals to the outside as second digital baseband signals.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input (second digital baseband signal) on the frequency conversion unit 15 side set in step S18, and outputs the selected signal to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 converts the rate of the second digital baseband signal input at the rate conversion rate set in step S18, and converts the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 31 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal, and outputs a measurement BER (step S12).

As described above, the signal quality measurement unit 19 measures the SNR of the received signal from the first digital baseband signal output from the AD conversion unit 14, and outputs the measured SNR as a measured SNR value (step S13).

The reception method selection unit 32 compares the measured SNR value output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S11 (step S14).

Here, since the measurement signal quality is higher than the reference signal quality, the reception method selection unit 32 outputs a method selection signal for selecting the zero IF method (step S19).

When the method selection signal for selecting the zero IF method output from the reception method selection unit 32 is input, the function block setting unit 21 sets the zero IF method for each functional block because it is currently a low IF method. It is decided to perform (step S20).

Next, the functional block setting unit 21 generates a setting signal for setting each functional block to the low IF method, and outputs the setting signal to each functional block (step S21).

The wireless reception device 30 starts the operation in the zero IF method by the processing in step S21.

Furthermore, the case where the measurement signal quality is lower than the reference signal quality (Yes in step S14) and the measurement BER is better than the reference BER (No in step S15) will be described.

Continue to receive RF signals from outside and perform wireless reception processing. Here, as described above, reception is performed by the zero IF method.

In the orthogonal demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S21. The mixers 123 and 124 mix the local oscillator 121 output, the phase-shifted local oscillation signal phase shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and generate a pair of baseband I and Q signals. Output. The amplifiers 125 and 126 amplify the pair of baseband I and Q signals described above, and output the amplified signals to the outside as a first analog baseband signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the passband set in step S21 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 digitally convert the input second analog baseband signal at the sampling rate set in step S21. The AD converter 14 outputs the digitally converted signal to the outside as a first digital baseband signal.

In the multiplexer unit 160, the pair of multiplexers 161 and 162 selects the input (first digital baseband signal) on the AD conversion unit 14 side set in step S21, and outputs the selected signal to the outside.

In the rate conversion unit 17, the pair of rate converters 171 and 172 convert the rate of the first digital baseband signal input at the rate conversion rate set in step S21, and convert the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 31 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal, and outputs a measurement BER (step S12).

As described above, the signal quality measurement unit 19 measures the SNR of the received signal from the first digital baseband signal that is the output of the AD conversion unit 14, and outputs the measured SNR as a measured SNR value (step S13). .

The reception method selection unit 32 compares the measured SNR value output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S11 (step S14).

The reception method selection unit 32 compares the measurement BER of the output of the demodulation / decoding processing unit 31 with the reference BER set in step S11 (step S15).

Then, the reception method selection unit 32 outputs a method selection signal for selecting the zero IF method (step S19).

When the method selection signal for selecting the zero IF method output from the reception method selection unit 32 is input, the functional block setting unit 21 does not change the setting for each functional block because it is currently the zero IF method (step S20).

The wireless reception device 30 continues to operate in the zero IF method by the processing in step S20.

Then, the same operation is continued, and the loop is exited when wireless reception is completed.

When the signal quality is poor (SNR is low) (Yes in step S14), the low IF method is expected to improve the reception performance with respect to the zero IF method from the zero IF method in which the reception performance may be deteriorated. Change to On the other hand, if the signal quality is good (SNR is high) (No in step S14), the low-IF method with high power consumption is changed to the zero-IF method that can be expected to reduce power consumption with respect to the low-IF method.

As described above, the radio reception device 30 according to the third embodiment of the present invention reduces the power consumption while maintaining the reception performance to some extent by changing the reception method based on the measured signal quality. It is possible to make it.

In this embodiment, in addition to the effects of the first embodiment, a bit error rate (BER) can be used when selecting a reception method. For this reason, there are moments when the SNR deteriorates in bursts, but it is expected that the accuracy of method selection will be improved, such as no extra switching occurring when the bit error rate (BER) is not so bad that the reception method is switched. The
(Fourth embodiment)
Next, a radio reception device 40 according to the fourth embodiment of the present invention will be described. In the fourth embodiment, a case where correction (compensation) is performed on a received signal in the zero IF method will be described.

FIG. 10 shows an example of a block configuration diagram of the receiving apparatus according to the present embodiment.

In FIG. 10, the wireless reception device 40 according to the fourth embodiment of the present invention adds a signal correction unit 165 between the AD conversion unit 14 and the frequency conversion unit 15 to the first embodiment, and the frequency The conversion unit 15 is changed to input the NCO parameter output from the signal correction unit 165. In the wireless reception device 40 according to the present embodiment, the multiplexer unit 160 is deleted, and the output (input selection setting) to the multiplexer unit 160 is deleted from the functional block setting unit 21.

In the fourth embodiment, it is possible to improve the reception performance of the zero IF method by performing correction by digital signal processing in the case of the zero IF method. As a result, the reference SNR for changing the method to the low IF method can be set lower, so that the time required for the low IF method is shortened and the power consumption is reduced.

Hereinafter, the wireless reception device 40 according to the fourth embodiment will be described in more detail. In FIG. 10, the configuration of parts other than the signal correction unit 165 is the same as that of the wireless reception device 10 according to the first embodiment, and therefore, the same elements are denoted by the same names and reference numerals, and detailed description thereof is omitted. The explanation was omitted.

The signal correction unit 165 includes a correction parameter calculation unit 166, a pair of adders 167 and 168, and a multiplier 169.

The signal correction unit 165 receives the I and Q signals output from the AD conversion unit 14 as inputs, subtracts the DC offset of the correction parameter calculation unit 166 output from the I and Q signals, and sets the weight coefficient of the correction parameter calculation unit 166 output as I. Multiply the signal and output as a corrected baseband signal. Further, the NCO parameter output from the correction parameter calculation unit 166 is output to the outside as it is.

The frequency conversion unit 41 includes an NCO (Numerically Controlled Oscillator) 411, a phase shifter 152, four multipliers 153 to 156, and a pair of adders 157 and 158.

The frequency conversion unit 41 receives the I and Q signals output from the signal correction unit 165 as input, and outputs the I and Q signals output from the signal correction unit 165, the NCO 151, and the phase shifter 152 output based on the NCO setting or NCO parameter. Frequency conversion is performed by complex multiplication of the complex signal. The frequency converting unit 41 outputs baseband I and Q signals (second digital baseband signals) subjected to frequency conversion.

The functional block setting unit 42 receives the method selection signal output from the reception method selection unit 20 as an input, and each operation of the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, the frequency conversion unit 41, and the rate conversion unit 17. A control signal for controlling the state is output.

The functional block setting unit 42 sets the frequency / gain setting (setting LG) of the local oscillator in the quadrature demodulation unit 12, sets the passband (setting B) in the low-pass filter unit 13, and sets the sampling frequency (settings) in the AD conversion unit 14. The control signal regarding S) is output. Further, the functional block setting unit 42 outputs a control signal related to NCO frequency setting (setting N) to the frequency conversion unit 41 and to a rate conversion rate setting (setting R) to the rate conversion unit 17.

Other than the signal correction unit 165, the frequency conversion unit 41, and the functional block setting unit 42 described above are the same as those in the first embodiment shown in FIG.

(Operation)
The operation of the wireless reception device 40 according to the fourth embodiment of the present invention will be described with reference to FIGS. Here, similarly to the description of the operation of the first embodiment, the case where the low IF method is selected and the case where the zero IF method is selected will be described in order.

First, the wireless receiver 40 is initially set by a host controller or the like (step S1). Here, it is assumed that reception is started by the zero IF method in order to reduce power consumption. The operations of the following functional blocks are not shown in the flowchart of FIG.

Appropriate settings for operating in the zero IF system corresponding to the radio standards received by the high-frequency unit 11, the quadrature demodulation unit 12, the low-pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 by the initial setting in step S1. Is done.

When the initial setting for the wireless receiving device 10 is completed, an RF signal input is started from the outside, and the wireless reception process is started. As described above, reception by the zero IF method is started here.

The high frequency unit 11 attenuates a signal other than the reception frequency band set in step S1 with respect to the input RF signal, amplifies the signal in the reception frequency band, and outputs a desired RF signal.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S1. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal shifted by 90 degrees by the phase shifter 122, and the input desired RF signal, and generate a pair of baseband I and Q signals. Output. The amplifiers 125 and 126 amplify the pair of baseband I and Q signals described above, and output the amplified signals to the outside as a first analog baseband signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S1 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 performs digital conversion on the input second analog baseband signal at the sampling rate set in step S1. The AD converter 14 outputs the digitally converted signal to the outside as a first digital baseband signal.

In the signal correction unit 165, in the zero IF method, the correction parameter calculation unit 166 calculates a correction parameter from the input I and Q signals, and outputs a DC offset, a weighting factor, and an NCO parameter (numerically controlled oscillation parameter). . A pair of adders 167 and 168 subtract the DC offset from the input I and Q signals. Multiplier 169 multiplies the input I signal and the weighting coefficient, and outputs the result together with the Q signal as a corrected baseband signal.

In the frequency conversion unit 41, the NCO 411 outputs a numerically controlled oscillation signal having a frequency based on the NCO parameter output from the correction parameter calculation unit 166 in the zero IF method. Multipliers 153 to 156 multiply the output of NCO 411 and the phase shift numerical control oscillation signal shifted by 90 degrees by phase shifter 152 and the corrected baseband signal. Adders 157 and 158 add and subtract two pairs of signals output from multipliers 153 to 156, respectively, and output the added and subtracted signals to the outside as second digital baseband signals.

In the zero IF method, since frequency conversion and phase rotation can be calculated using the same arithmetic unit, the frequency conversion unit 41 performs phase rotation processing of the received signal based on the parameters estimated by the signal correction unit 165. Do. As will be described later, in the low IF method, the frequency conversion unit 41 is used for frequency conversion as in the first and second embodiments.

In the rate conversion unit 17, the pair of rate converters 171 and 172 convert the rate of the first digital baseband signal input at the rate conversion rate set in step S1, and convert the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 18 performs demodulation processing / decoding processing corresponding to the wireless standard on the input third digital baseband signal.

Here, the signal quality measurement unit 19 measures the signal-to-noise power ratio (SNR) as the signal quality of the received signal from the first digital baseband signal output from the AD conversion unit 14, and the measured SNR is measured signal quality. It outputs as (measured SNR value) (step S2).

Hereinafter, first, a case where the measurement signal quality is lower than the reference signal quality (in the case of Yes in step S3 in FIG. 6) will be described. At this stage, reception is performed by the zero IF method as described above.

The reception method selection unit 20 compares the measurement signal quality (measurement SNR value) output from the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is lower than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the low IF method (step S4).

When the method selection signal for selecting the low IF method output from the reception method selection unit 20 is input, the functional block setting unit 42 is currently in the zero IF method, and therefore sets the low IF method for each functional block. It is decided to perform (step S5).

Here, if it is the low IF method, the current loop is terminated without changing the method.

Next, the functional block setting unit 42 generates a setting signal for setting each functional block to the low IF method, and outputs the setting signal to each functional block (step S6).

By the processing in step S6, appropriate settings for operating in the low IF system corresponding to the radio standards received by the high frequency unit 11, the quadrature demodulation unit 12, the low pass filter unit 13, the AD conversion unit 14, and the rate conversion unit 17 are set. Done. Then, the wireless reception device 40 starts the operation in the low IF method and ends the current loop.

Next, a case where the measurement signal quality is higher than the reference signal quality will be described (No in step S3). Continue to receive an RF signal from the outside and perform wireless reception processing. Here, as described above, reception is performed by the low IF method.

In the quadrature demodulator 12, the local oscillator 121 outputs a local oscillation signal having the frequency set in step S6. The mixers 123 and 124 mix the output of the local oscillator 121, the phase-shifted local oscillation signal phase-shifted 90 degrees by the phase shifter 122, and the input desired RF signal, and a pair of intermediate frequency (IF) I's. , Q signal is output. In addition, the amplifiers 125 and 126 amplify the above-described pair of intermediate frequency (IF) I and Q signals and output the amplified signals to the outside as first analog baseband signals. A signal obtained by amplifying the I and Q signals is also an intermediate frequency (IF) signal, but is referred to as a baseband signal in order to have the same name as the above signal.

In the low-pass filter unit 13, the pair of low- pass filters 131 and 132 pass the pass band set in step S 6 with respect to the input first analog baseband signal, and externally pass as the second analog baseband signal. Output to.

In the AD conversion unit 14, the pair of AD converters 141 and 142 performs digital conversion on the input second analog baseband signal at the sampling rate set in step S6. The AD converter 14 outputs the digitally converted signal to the outside as a first digital baseband signal.

In the signal correction unit 165, in the low IF method, the correction parameter calculation unit 166 does not calculate the correction parameter from the input I and Q signals, outputs 0 as the DC offset, 1 as the weighting factor, and does not output the NCO parameter. A pair of adders 167 and 168 subtract the DC offset from the input I and Q signals. Since 0 is subtracted here, there is no change in the value at the input / output of the adders 167 and 168. The multiplier 169 multiplies the input I signal by the weighting factor, and outputs it as a corrected baseband signal together with the Q signal. Here, since 1 is multiplied, there is no change in the value at the input / output of the multiplier 169.

In the frequency converter 41, the NCO 411 outputs a numerically controlled oscillation signal having a frequency based on the NCO setting (step S6) output from the functional block setting unit 42 in the low IF method. Multipliers 153 to 156 multiply the NCO 411 output and the phase shift numerical control oscillation signal shifted by 90 degrees by the phase shifter 152 and the corrected baseband signal. Adders 157 and 158 add and subtract two pairs of signals output from multipliers 153 to 156, and output the resulting signal as a second digital baseband signal.

In the zero IF method, since frequency conversion and phase rotation can be calculated using the same computing unit, the frequency conversion unit 41 performs phase rotation processing of the received signal based on the parameters estimated by the signal correction unit 165. As will be described later, in the low IF method, the frequency conversion unit 41 is used for frequency conversion as in the first and second embodiments.

In the rate conversion unit 17, the pair of rate converters 171 and 172 converts the rate of the second digital baseband signal input at the rate conversion rate set in step S6, and converts the converted signal to the third digital signal. Output to the outside as a baseband signal.

The demodulation / decoding processing unit 18 performs demodulation processing and decoding processing corresponding to the wireless standard on the input third digital baseband signal.

As described above, the signal quality measurement unit 19 measures the SNR of the received signal from the first digital baseband signal that is the output of the AD conversion unit 14, and outputs the measured SNR as a measured SNR value (step S2). .

The reception method selection unit 20 compares the measured SNR value of the output of the signal quality measurement unit 19 with the reference signal quality (reference SNR value) set in step S1 (step S3).

Here, since the measurement signal quality is higher than the reference signal quality, the reception method selection unit 20 outputs a method selection signal for selecting the zero IF method (step S7).

When the method selection signal for selecting the zero IF method output from the reception method selection unit 20 is input, the functional block setting unit 42 sets the zero IF method for each functional block because it is currently the low IF method. Is determined (step S8).

Next, the functional block setting unit 42 generates a setting signal for setting each functional block to the low IF method, and outputs the setting signal to each functional block (step S9).

The wireless receiver 40 starts the operation in the zero IF method by the process of step S9.

続 け Continue the same operation and exit the loop when wireless reception ends.

As described above, when the signal quality is poor (SNR is low) (Yes in step S3), the reception performance can be deteriorated from the zero IF method in which the reception performance may be deteriorated. Change to method. On the other hand, when the signal quality is good (SNR is high) (No in step S3), the low IF method with high power consumption is changed to the zero IF method that can reduce power consumption with respect to the low IF method.

As described above, according to the wireless reception device 40 according to the fourth embodiment of the present invention, the power consumption is maintained while maintaining the reception performance to some extent by changing the reception method based on the measured signal quality. Can be reduced. In addition to the effects of the first embodiment described above, this embodiment improves the reception performance of the zero IF method with a small circuit scale addition by performing compensation by signal processing in the case of the zero IF method. It becomes possible to make it. As a result, it is possible to set the reference SNR for changing the method to the low IF method to a lower value, so that the power consumption can be further reduced.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2013-122437 filed on June 11, 2013, the entire disclosure of which is incorporated herein.

DESCRIPTION OF SYMBOLS 1, 10, 200, 30, 40 Wireless receiver 2 Reception system setting means 5 Zero IF receiver 6 Low IF receiver 11 High frequency part 12 Orthogonal demodulation part 13 Low pass filter part 14 AD conversion part 15, 41 Frequency conversion part 16 Reception Method switching unit 17 Rate conversion unit 18, 31 Demodulation / decoding processing unit 19 Signal quality measurement unit 20, 32 Reception method selection unit 21, 26, 42 Function block setting unit 111 Band pass filter 112 Low noise amplifier 113, 131 Low pass filter 121 Local Oscillator 122, 152 Phase shifter 123 Mixer 125 Amplifier 141 AD converter 151, 411 NCO
153, 154, 169 Multiplier 157, 167 Adder 160 Multiplexer 161 Multiplexer 165 Signal corrector 166 Correction parameter calculator 171 Rate converter

Claims (10)

1. Receiving means for generating a digital signal based on the received signal;
   Measuring the signal quality of the digital signal generated based on the received signal to generate a measurement signal quality, and receiving the received signal based on a comparison result between the generated measurement signal quality and a preset reference signal quality A reception method setting unit that generates a method selection signal by selecting a method, generates a control signal in accordance with the method selection signal at the time when the signal quality changes, and outputs the generated control signal to the reception unit And
   The receiving means includes
   A wireless reception device that switches the reception method to a method with different power consumption according to the control signal.
2. Signal quality measuring means for measuring the signal quality of the digital signal to generate the measurement signal quality and outputting the generated measurement signal quality;
   Receiving method selection means for generating the method selection signal by selecting the reception method based on a comparison result between the reference signal quality and the measurement signal quality, and outputting the generated method selection signal;
   The radio reception apparatus according to claim 1, further comprising: a function block setting unit that outputs the control signal that controls setting of a function block group that executes signal processing according to the method selection signal.
3. High-frequency means for receiving a high-frequency signal included in the received signal, attenuating a high-frequency signal other than the reception frequency band in the input high-frequency signal and amplifying the high-frequency signal included in the reception frequency band;
   A quadrature demodulating means that has a local oscillator and inputs the high-frequency signal output by the high-frequency means and converts it into a first analog baseband signal consisting of an intermediate frequency signal or a baseband I signal and a Q signal;
   Low-pass filter means for taking the first analog baseband signal as an input, band-limiting the input first analog baseband signal and converting it to a second analog baseband signal;
   Analog-to-digital conversion means for inputting the second analog baseband signal and converting it into a first digital baseband signal;
   A frequency converting means having a numerically controlled oscillator, which receives the first digital baseband signal and converts the frequency into a second digital baseband signal;
   A reception method switching means for switching the reception method so that one of the first and second digital baseband signals is selected as a signal to be used at a later stage than the frequency conversion means;
   A rate at which the first or second digital baseband signal is input, and the input first or second digital baseband signal is reduced to a desired sampling rate and converted to a third digital baseband signal. Conversion means;
   Demodulation and decoding processing means for inputting the third digital baseband signal and performing demodulation and decoding processing;
   The signal quality measuring means includes
   Outputting the measurement signal quality generated by measuring the signal quality of the first digital baseband signal;
   The reception method selection means includes
   Selecting the reception method based on a comparison result between the reference signal quality and the measurement signal quality and outputting the method selection signal;
   The functional block setting means includes
   At the time when the signal quality has changed, at least the quadrature demodulation means, the low-pass filter means, the analog-digital conversion means, the frequency conversion means, and the rate conversion means according to the method selection signal The radio reception according to claim 1 or 2, wherein the control signal for controlling an operation state of the functional block group including the control block is generated, and each functional block included in the functional block group is controlled in block units using the control signal. apparatus.
4. The reception method selection means includes
   If the measurement signal quality is higher than the reference signal quality, select to input the first digital baseband signal to the rate conversion means;
   The radio reception apparatus according to claim 3, wherein when the measurement signal quality is lower than the reference signal quality, the first digital baseband signal is selected to be input to the frequency conversion unit.
5. The functional block setting means includes
   For the quadrature demodulating means, setting regarding the oscillation frequency of the local oscillator that the quadrature demodulating means has and the gain for the input signal,
   For the low-pass filter means, setting related to the passband setting of the input signal,
   Setting the sampling frequency for converting the second analog baseband signal into the first digital baseband signal for the analog-digital conversion means;
   For the frequency conversion means, setting for the transmission frequency of the numerically controlled oscillator that the frequency conversion means has,
   The radio reception apparatus according to claim 3 or 4, wherein a setting relating to a rate conversion rate of a sampling rate of the input signal is made to the rate conversion means.
6. The reception method switching means is
   The first and second digital baseband signals are input, and one of the first and second digital baseband signals is selected according to the control signal relating to the input setting generated by the functional block setting means. The radio reception apparatus according to any one of claims 3 to 5, including a multiplexer.
7. The functional block setting means sets the frequency conversion means with respect to the oscillation frequency and clock gating control of the numerically controlled oscillator,
   The clock supply to the frequency conversion unit is stopped according to the setting related to the clock gating control when the measurement signal quality is higher than the reference signal quality. The wireless receiving device described.
8. The demodulation / decoding processing means includes
   The bit error rate is measured by performing demodulation / decoding processing corresponding to the radio standard of the high-frequency signal on the input third digital baseband signal with the third digital baseband signal as input, Output the measured bit error rate, which is the measured bit error rate,
   The reception method selection means includes
   The reception method is selected by comparing the reference signal quality and the measurement signal quality, and comparing a preset reference bit error rate and the measurement bit error rate, and outputting the method selection signal. The wireless reception device according to any one of 3 to 7.
9. The reception method switching means is
   Inputting the first digital baseband signal, calculating a DC offset, a weighting factor and a numerically controlled oscillation parameter based on the input first digital baseband signal;
   Subtracting the DC offset from the I and Q signals converted to the first digital baseband signal;
   Multiplying the I signal minus the DC offset by the weighting factor;
   Generating a corrected baseband signal obtained by combining the Q signal obtained by subtracting the DC offset and the I signal multiplied by the weighting coefficient after subtracting the DC offset;
   Output the numerically controlled oscillation parameter to the numerically controlled oscillator that the frequency conversion means has,
   The radio reception apparatus according to claim 3, wherein the correction baseband signal is output to the frequency conversion unit.
10. Generate a digital signal based on the received signal,
    Measure the signal quality of the digital signal generated based on the received signal to generate the measurement signal quality,
    A method selection signal is generated by selecting a reception method of the reception signal based on a comparison result between the generated measurement signal quality and a preset reference signal quality,
    When the signal quality changes, a control signal is generated according to the method selection signal,
    A wireless reception method for switching the reception method to a method with different power consumption according to the control signal.

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