JP2008167371A - Receiver, and receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phase modulation type receiver capable of reducing power consumption to a minimum. <P>SOLUTION: The present invention relates to the phase modulation type signal receiving device 10 comprising an RF signal processing unit 100 for receiving a transmitted signal modulated by a predetermined modulation system (phase modulation system) and down-converting the received signal, and a baseband signal processing section 200 for demodulating digital data on the basis of a state of modulation, for each symbol term, of the signal down-converted by the RF signal processing section 100, wherein a control section 230 which controls so as to intermittently operate the RF signal processing section 100 only during a predetermined partial period in each symbol term of the phase modulated signal, is included. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a receiving apparatus and a receiving method, and more particularly to improvement of characteristics related to power saving of the receiving apparatus and the receiving method.

Conventionally, various proposals have been made to reduce the power consumption of a receiving device and to suppress the consumption of a battery as a power source. For example, there is a proposal to suppress the power consumption of the battery by causing the PLL local oscillation circuit of the FSK receiver to operate intermittently corresponding to the phase synchronization holding state (see, for example, Patent Document 1).
In this proposal, when the line frequency is set according to the area like the selective call receiver, the selective call receiver in which the frequency of the local oscillation circuit is fixed cannot be called, whereas the PLL is not capable of calling. In the selective call receiver using the local oscillation circuit, it is possible to call without any problem, but the PLL oscillation circuit that provides the local oscillation frequency performs PLL control compared to the fixed crystal oscillation circuit. The technical problem is that the current increases.

In order to solve this technical problem, a phase-locked loop for the FSK modulated wave is secured and the FSK
PLL local oscillating means for outputting the first local oscillation frequency necessary for demodulating the modulated wave, and the first intermediate frequency by the first local oscillation frequency is converted to the second intermediate frequency by the second local oscillation frequency. Control signal when an average value of a signal demodulated by the demodulating means indicates a phase-locked deviation state by a phase-locked loop in a double superheterodyne type FSK receiver including a demodulating means for demodulating and extracting a baseband signal A predetermined control signal is output from the detection means, and bit synchronization and frame synchronization are detected based on the signal demodulated by the demodulation means, and a synchronization signal is output from the synchronization detection means. These control signals are output by the PLL intermittent operation means. While receiving the outputs of the detection means and the synchronization detection means, the PLL local oscillation means confirms the phase synchronization state in the absence of the control signal input. The first local oscillation frequency is maintained in a state where the phase locked loop operation of the PLL local oscillation means is stopped, while the phase locked loop operation is activated when the control signal is input. 1 local oscillation frequency is maintained.

That is, by intermittently operating the PLL circuit according to the phase synchronization pull-in state of the PLL circuit, the consumption current of the PLL circuit is reduced at the time of reception, and the battery life is improved.
JP-A-6-104941 (paragraph 0034 to paragraph 0036, FIG. 3)

However, even if the PLL circuit is intermittently operated depending on the phase synchronization pull-in state of the PLL circuit, the power saving effect is still limited. Incidentally, in the technique proposed in Patent Document 1, the phase-locked loop operation is stopped only during the period in which the “control signal” in this proposal is interrupted, and so-called down-conversion processing using a signal of the local oscillation frequency is received. It continues for the whole period, and the electric power required for the duration is always consumed.
The present invention has been made in view of such circumstances, and it is an object of the present invention to make it possible to significantly reduce power consumption in a receiving apparatus and a receiving method that receive a transmitted signal modulated by a predetermined modulation method. And

In order to solve the above problems, the present application proposes the following technologies.
(1) An RF signal processing unit that receives a transmitted signal that has been modulated by a predetermined modulation method, down-converts the received signal, and modulation for each symbol period of the signal down-converted by the RF signal processing unit. A baseband signal processing unit that demodulates digital data based on a state, and a device for receiving a transmitted signal,
A control unit that controls the RF signal processing unit to operate intermittently limited to a predetermined partial period in each symbol period of the transmitted signal that has been modulated by the predetermined modulation method; A receiving device.

In the receiving apparatus of (1) above, the RF signal processing unit operates intermittently only in a predetermined partial period in each symbol period of the transmitted signal that has been modulated by the predetermined modulation method. A signal (carrier phase modulation status) is detected and demodulated in each partial period in each successive symbol period, and a baseband signal is demodulated, while an RF signal is transmitted in periods other than these partial periods in each successive symbol period. Since the processing unit is paused, power consumption is greatly suppressed.

(2) The control unit selects a period including a central position in each symbol period as the predetermined partial period in each symbol period of the transmitted signal modulated by the predetermined modulation method. (1) receiving apparatus.
In the receiver of (2) above, particularly in the receiver of (1), the RF signal processor is operated intermittently in such a manner that the period including the central position in each of the sequential symbol periods described above is selectively operated. Therefore, while the power consumption is significantly suppressed, there is a high possibility that highly reliable demodulation with few errors can be performed.

(3) The baseband signal processing unit detects quality related to the signal received by the RF signal processing unit, and the control unit performs intermittent operation of the RF signal processing unit according to the detected quality value. The receiver according to any one of (1) to (2), which controls a general operation mode.
In the receiver of (3) above, in particular, in the receiver of any one of (1) to (2), a detected quality value, typically, for example, a BER (Bit Error Rate) value. Accordingly, since the intermittent operation mode of the RF signal processing unit is controlled, it is possible to perform demodulation with high reliability without causing a decrease in BER.

(4) The RF signal processing unit includes a PLL type local frequency signal generation unit configured to include a voltage controlled oscillation circuit, a phase synchronization circuit, and a buffer, and generate a local frequency signal.
And the said control part controls so that the said voltage control oscillation circuit is intermittently operated among the said local frequency signal production | generation parts, The receiving apparatus in any one of (1)-(3) characterized by the above-mentioned.
In the receiver of (4) above, in particular, in the receiver of any one of (1) to (3), a voltage-controlled oscillator circuit with particularly high power consumption among the receivers as a whole is intermittent in each successive symbol period. By activating the system and resting it for other periods, the power consumption is greatly suppressed, and the configuration becomes simpler than when the entire RF signal processing unit is operated intermittently.

(5) The RF signal processing unit includes a PLL type local frequency signal generation unit configured to include a voltage-controlled oscillation circuit, a phase synchronization circuit, and a buffer, and generate a local frequency signal.
And the said control part is controlled to operate | move the said buffer intermittently among the said local frequency signal generation parts, The receiving apparatus in any one of (1)-(3) characterized by the above-mentioned.
In the receiver of the above (5), in particular, in the receiver of any one of (1) to (3), a buffer with relatively large power consumption is intermittently provided in each successive symbol period. By operating and resting for periods other than the operating period, power consumption is greatly suppressed, and the configuration becomes simpler than intermittently operating other parts or the whole of the RF signal processing unit.

(6) The RF signal processing unit includes a PLL-based local frequency signal generation unit configured to include a voltage-controlled oscillation circuit, a phase synchronization circuit, and a buffer, and generate a local frequency signal.
The control unit controls the entire local frequency signal generation unit including a voltage controlled oscillation circuit, a phase synchronization circuit, and a buffer to operate intermittently (1) to (
3) Any one receiving apparatus.
In the receiver of (6) above, in particular, in the receiver of any one of (1) to (3), the entire local frequency signal generator including the voltage controlled oscillation circuit, the phase synchronization circuit, and the buffer is intermittently provided. Power consumption can be extremely effectively suppressed by operating and resting for periods other than the operation period.

(7) The receiving apparatus according to any one of (1) to (2), wherein the control unit performs control so that the entire RF signal processing unit is operated intermittently.
In the receiver of (7) above, in particular, in the receiver of any one of (1) to (2), the entire RF signal processing unit is intermittently operated during each successive symbol period, and is rested during other periods. Therefore, an extremely large power consumption suppressing effect can be obtained.

(8) The receiving device according to any one of (1) to (7), wherein the control unit is provided in the baseband signal processing unit.
In the receiver of (8) above, in particular, in the receiver of any one of (1) to (7), since the control unit is provided in the baseband signal processing unit, it is easy to reduce the size.

(9) The control unit is set as one functional unit in a system controller that comprehensively manages the entire system of the receiving apparatus including the RF signal processing unit and the baseband signal processing unit. The receiving device according to any one of (1) to (7).
In the receiving device of (9) above, in particular, in the receiving device of any one of (1) to (7), the control unit controls the entire receiving device system including the RF signal processing unit and the baseband signal processing unit. Since it is set as a single function unit in the system controller managed by the system controller, it is possible to perform highly functional control.

(10) An RF signal processing unit that receives a transmitted signal that has been modulated by a predetermined modulation method and down-converts the received signal; and a modulation unit for each symbol period of the signal down-converted by the RF signal processing unit. A baseband signal processing unit that demodulates digital data based on a state, and a device for receiving a transmitted signal,
A control unit for controlling the baseband signal processing unit to operate intermittently limited to a predetermined partial period in each symbol period of the transmitted signal modulated by the predetermined modulation method; A receiving device.

In (10) above, since the baseband signal processing unit operates intermittently only in a predetermined partial period in each symbol period of the transmitted signal that has been modulated by the predetermined modulation method, The baseband signal is demodulated by detecting the signal (carrier phase modulation status) for each of the partial periods in each of the symbol periods, while the baseband signal is in a period other than these partial periods in each successive symbol period Since the processing unit is paused, power consumption is greatly suppressed.

(11) The control unit is set as one functional unit in a system controller that comprehensively manages the entire system of the receiving apparatus including the RF signal processing unit and the baseband signal processing unit. (10).
In the receiving device of (11), particularly in the receiving device of (10), the control unit is included in a system controller that comprehensively manages the entire system of the receiving device including the RF signal processing unit and the baseband signal processing unit. Since it is set as one functional unit, it is possible to perform highly functional control.

(12) RF signal processing for receiving a transmitted signal modulated by a predetermined modulation method and down-converting the received signal is performed in a predetermined symbol period of the transmitted signal modulated by the predetermined modulation method. The reception method is characterized in that it is executed intermittently in a limited period of time.
In the reception method of (12), the signal (phase modulation state of the carrier wave) is detected for each partial period in each successive symbol period and the baseband signal is demodulated, while these signals in each successive symbol period are demodulated. Since the RF signal processing is suspended in a period other than the partial period, power consumption is greatly suppressed.

(13) Receiving a transmitted signal modulated by a predetermined modulation method, performing RF signal processing on the received signal, and demodulating digital data based on the modulation state for each symbol period of the down-converted signal A receiving method characterized in that baseband signal processing is executed intermittently limited to a predetermined partial period in each symbol period of a transmitted signal that has been modulated by the predetermined modulation method.
In the reception method of (13) above, a signal (carrier phase modulation status) is detected for each partial period in each successive symbol period and the baseband signal is demodulated, while these in each successive symbol period. Since baseband signal processing is paused during periods other than the partial period, power consumption is greatly suppressed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The transmitted signal in the disclosure of the present specification is a signal that is modulated and transmitted by a predetermined modulation method, and examples of the modulation method include AM, FM, PM, ASK, PSK, FSK, and QA.
It is possible to apply methods such as M, DM, MSK, CCK, PWM, PAM, PDM, PPM, and PCM. In the following description, BPSK, which is one of PSK among the above examples, is used. Embodiments using the above will be described in detail.
FIG. 1 is a waveform diagram showing signals and operation timing of an apparatus for explaining the principle of the present invention.

FIG. 1A is a waveform diagram of a carrier that carries a transmitted signal by a phase modulation method.
FIG. 1B is a waveform diagram of a baseband signal carried by the carrier wave of FIG. 1A, and FIG. 1C is a carrier wave that has undergone phase modulation by the baseband signal of FIG. 1B. (BPS
1 (D) is a waveform diagram of the K system signal), and FIG. 1 (D) shows the operating state of the corresponding part of the receiving apparatus of the present invention in order to recover the baseband signal of FIG. 1 (B) from the signal of FIG. 1 (C). It is a figure showing the timing to make.

The principle of the present invention will be described with reference to FIG. 1. Prior to that, the formation of a conventional phase modulation signal will be described with reference to FIG.
FIG. 14 is a waveform diagram showing a signal of a BPSK system which is one of general phase modulation systems. In FIG. 14, for convenience of explanation, one period of the signal waveform is made larger than the actual signal waveform so that the state of the phase change of the waveform can be easily understood (therefore, the frequency is deliberately lowered). It is expressed so that the waveform for two cycles fits in one symbol period.

14A is a waveform diagram of a baseband signal, FIG. 14B is a waveform diagram of a carrier wave carrying the baseband signal of FIG. 14A, and FIG. 14C is a waveform diagram of FIG. It is a wave form diagram of the carrier wave which received the phase modulation by the baseband signal of (A).
As shown in FIG. 14, H or L (1 or 0) of the baseband signal of FIG.
Accordingly, as shown in FIG. 14C, the carrier wave of FIG. 14B is phase-shifted (inverted) by 180 degrees.

In FIG. 14, for convenience of explanation, the data rate and the frequency of the carrier wave are depicted so as not to differ so much, but actually, FIG. 1C is expressed relatively close to the actual phenomenon. Thus, for example, the frequency of CDMA2000 in Japan is 1.2288 MHz with respect to a carrier of 860.95 MHz, and therefore, the baseband signal in FIG. That is, one symbol period corresponds to a period of approximately 700 periods of the carrier wave.

The present invention pays attention to this point, for example, a signal of a phase modulation system (BPSK) as shown in FIG.
RF signal processing for receiving and downconverting the received signal corresponds to the chip rate corresponding to each symbol period of the signal according to this phase modulation method (ie, the baseband signal in FIG. 1B). , Intermittently limited to a predetermined partial period (each limited period of sequential symbol periods) as represented by the timing waveform diagram of FIG. It is characterized by being executed.

In the present invention, in this way, the signal ((
While the baseband signal is demodulated by detecting the phase modulation state of the carrier wave, the RF signal processing is paused in periods other than these partial periods in each successive symbol period, so that power consumption is greatly suppressed. The
FIG. 2 is a block diagram showing a receiving device 10 as an embodiment of the present invention. This receiving device is a receiving device for a transmitted signal, and receives an RF signal processing unit 100 that receives a signal (RF signal) of a phase modulation method that is an example of a modulation method, and down-converts the received signal, and an RF signal Baseband signal processing unit 200 that demodulates digital data based on the modulation state (phase change) for each symbol period of the signal down-converted by the processing unit 100
And.

The baseband signal processing unit 200 converts the down-converted signal supplied from the RF signal processing unit 100 into a digital signal, decodes the signal digitized by the AD conversion unit 210, and decodes the original signal While reproducing the audio and other data D, the signal processing unit 220 that detects the BER (bit error rate) related to the reproduction and the modulation by a predetermined modulation method according to the BER detected by the signal processing unit 220 In each symbol period of the transmitted signal, RF is limited to a predetermined partial period as described above with reference to FIG.
A control unit 230 that controls the signal processing unit 100 to operate intermittently is provided.

In the receiving apparatus of the embodiment of FIG. 2, the RF signal processing unit 100 is intermittently operated only in a predetermined partial period in each symbol period of a transmitted signal that has been modulated by a predetermined modulation method. Therefore, in each sequential symbol period, for example, a signal (phase modulation state of a carrier wave) is detected for each partial period as described above with reference to FIG. In periods other than these partial periods in each successive symbol period, RF
Since the signal processing unit is at rest, power consumption is greatly suppressed.

As understood from the timing waveform of FIG. 1D, in this embodiment, the RF signal processing unit 100 operates intermittently in such a manner that a period including the center position in each successive symbol period is selectively operated. As a result, the power consumption is greatly suppressed, while the detection of the phase modulation signal (RF signal) has a high possibility of performing reliable demodulation with few errors.

In the normal case, the BER is good when the period including the center position in each symbol period is selected as the timing of the detected period and the phase of the transmitted signal modulated by a predetermined modulation method is detected. Therefore, as in the configuration described with reference to FIG. 2, in accordance with the BER detected by the signal processing unit 220, within each symbol period of the transmitted signal modulated by a predetermined modulation method, The timing for operating the RF signal processing unit 100 to detect the phase is expected to be a period including the central position in each symbol period, but the idea of the present invention is not limited to this. Absent.

That is, according to the BER detected by the signal processing unit 220, even if the RF signal processing unit 100 is operated at a timing that does not necessarily include the center position in each symbol period, the signal is received while maintaining a required BER. It can also be expected to demodulate the received signal.
In any case, the degree of the effect of suppressing the power consumption according to the present embodiment is, for example, FIG.
This is an outstanding one that can be understood intuitively from the duty ratio in the timing waveform.

(First embodiment)
FIG. 3 is a block diagram showing a receiving apparatus 11 as a first example of the present invention, which is a more specific form of the above-described embodiment. 3 corresponding to those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
In FIG. 3, an RF signal processing unit 100 includes a low-noise amplifier (LNA in the figure and in the following description) 110 that receives and amplifies the RF signal, and a mixer 120 that mixes the output of the LNA 110 with a local frequency signal and down-converts it. An amplifier circuit 140 that amplifies the signal that has passed through the band-pass filter (BPF in the figure and in the following description) 130 and outputs the amplified signal to the next-stage baseband signal processing unit 200; And a PLL local frequency signal generator 150 for generating a frequency signal.

The local frequency signal generation unit 150 includes a voltage controlled oscillation circuit (VCO in the figure and in the following description) 151, a phase synchronization circuit 152, and a buffer 153.
In the embodiment of FIG. 3, the above-described control unit 230 of the baseband signal processing unit 200 includes the VCO of the PLL local frequency signal generation unit 150 of the RF signal processing unit 100 described above.
151 is controlled to operate intermittently.

Of the above-described PLL system local frequency signal generation unit 150 in the RF signal processing unit 100, the VCO 151 having particularly high power consumption is intermittently operated in each successive symbol period, and other periods. By stopping, the power consumption is greatly suppressed, and the configuration is simpler than the entire RF signal processing unit is operated intermittently.

(Second embodiment)
FIG. 4 is a block diagram showing a receiving apparatus 12 as a second example of the present invention, which is a more specific form of the above-described embodiment. In FIG. 4, corresponding parts to those in FIGS. 2 and 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
In the embodiment of FIG. 4, the above-described control unit 230 of the baseband signal processing unit 200 operates the buffer 153 intermittently in the above-described PLL local frequency signal generation unit 150 of the RF signal processing unit 100. To control.

Among the entire receiver 12, among the above-described PLL local frequency signal generator 150 in the RF signal processor 100, the buffer 153 having relatively large power consumption is intermittently operated and is rested for other periods. Power consumption is greatly suppressed, and RF
The configuration is simpler than when other parts or the whole of the signal processing unit 100 are operated intermittently.

(Third embodiment)
FIG. 5 is a block diagram showing a receiving apparatus 13 as a third example of the present invention in which the above-described embodiment is made more concrete. 5 corresponding to those in FIGS. 2 and 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
In the embodiment of FIG. 5, the above-described control unit 230 of the baseband signal processing unit 200 provides its VCO1 to the above-described PLL local frequency signal generation unit 150 of the RF signal processing unit 100.
51, and the local frequency signal generation unit 150 including the phase synchronization circuit 152 and the buffer 153 are controlled to operate intermittently.
In the embodiment of FIG. 5, the entire local frequency signal generator 150 including the VCO 151, the phase synchronization circuit 152, and the buffer 153 is intermittently operated, and the power consumption is extremely effective by resting for periods other than the operation period. Can be suppressed.

(Fourth embodiment)
FIG. 6 is a block diagram showing a receiving apparatus 14 as a fourth example of the present invention, which is a more specific form of the above-described embodiment. In FIG. 6, corresponding parts to those in FIGS. 2 and 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
In the embodiment of FIG. 6, the control unit 230 described above of the baseband signal processing unit 200 controls the RF signal processing unit 100 to operate intermittently.

FIG. 7 is a block diagram showing in more detail the configuration of the local frequency signal generation unit 150 in the RF signal processing unit 100 in FIGS.
In FIG. 7, reference numeral 1500 is newly assigned to the PLL local frequency signal generator. The local frequency signal generation unit 1500 includes a VCO 1510, a phase synchronization circuit 1520, and an output buffer 1530.

The phase synchronization circuit 1520 divides the signal supplied from the VCO 1510.
1 and a phase frequency comparator / charge pump 1522 for comparing the frequency and phase of the output of the frequency divider 1521 with a reference signal Sr supplied from an external reference frequency generator such as a crystal oscillator (not shown), Filter output of comparator / charge pump 1522 to VCO
And LPF 1523 supplied to 1510.

FIG. 8 is a block diagram illustrating a configuration example of the VCO 1510 of FIG. VCO 151 in FIG.
0a has a feedback loop configuration in which the output of the NAND circuit 1515 connected in the subsequent stage of the cascade connection of the two-stage inverter 1511 and the inverter 1512 is fed back to the inverter 1511 in the previous stage, and the baseband signal Oscillation and stop of the VCO 1510 are controlled by the control signal Sc1 supplied from the above-described control unit 230 of the processing unit 200.

That is, in the circuit of FIG. 8, the control signal S supplied to one input terminal of the NAND circuit 1515.
When c1 is high (H), the NAND circuit 1515 receives a signal supplied to the other input terminal.
8 functions as an inverter, so that the entire VCO 1510a in FIG. 8 operates as an oscillation circuit using a three-stage inverter.
Further, the control signal Sc1 supplied to one input terminal of the NAND circuit 1515 is low (L).
At this time, the VCO 1510a in FIG. 8 maintains the stopped state because the output of the NAND circuit 1515 always functions as high (H) with respect to the signal supplied to the other input terminal.

In the circuit of FIG. 8, the NAND circuit 1515 is inserted in the feedback loop. However, a NOR circuit (not shown) may be applied instead of the NAND circuit 1515.
When the NOR circuit is applied in this way, the control signal Sc1 supplied to one input terminal.
8 operates in such a manner that the output of the NOR circuit is always low (L) with respect to the signal supplied to the other input terminal, so that the VCO 1510a in FIG. 8 maintains the stopped state. On the other hand, when the control signal Sc1 supplied to one input terminal of the NOR circuit is low (L),
Since the NOR circuit functions as an inverter, the entire VCO 1510a in FIG. 8 operates as an oscillation circuit using a three-stage inverter. In FIG. 8, an inverter oscillation circuit having a total of three stages is taken as an example, but the number of stages is optimally selected depending on the configuration.

FIG. 9 is a block diagram showing another configuration example of the VCO 1510 of FIG. VCO1 in FIG.
510b has a feedback loop configuration that supplies the output of the last stage inverter 1513 in the cascade connection of the three stages of inverters 1511, 1512, and 1513 to the input terminal of the first stage inverter 1511. Switching between the operation and stop of the VCO 1510b is controlled by controlling the power supply to the inverters 1511, 1512 and 1513 by the control signal Sc2 supplied from the control unit 230 described above. In FIG. 9, a total of three stages of inverter oscillation circuits are taken as an example, but the number of stages is optimally selected depending on the configuration.

FIG. 10 is a diagram for explaining a state of timing adjustment for operating the entire RF signal processing unit 100 or its corresponding part in each of the embodiments described above.
FIG. 10A is a diagram illustrating a symbol period Td that is a delimiter of data units in a phase modulation signal, and each symbol period Td is a data unit interval that is one chip in a CDMA signal.

FIG. 10B is a diagram illustrating the timing of operating the entire RF signal processing unit 100 or its corresponding part in each symbol period Td. Each rising position in the pulse-like waveform of FIG. 10B is a timing at which the RF signal processing unit 100 (or its corresponding part) is turned on (operated), and a period of time width Tw that continues to rise in the sequential symbol period Td. Is the on (operation) duration.
In one embodiment of the present invention, each rising position and on (operation) duration Tw
Are controlled based on the BER value detected by the signal processing unit 220 described above.

FIG. 11 is a block diagram showing one configuration example for controlling the timing for turning on (operating) the RF signal processing unit 100 (or its corresponding part). This timing control is
This is performed by controlling the oscillation operation of the PLL local frequency signal generation unit 1500 described above. In FIG. 11, the corresponding parts to those in FIG. 7 are indicated by the same reference numerals. is there.

In FIG. 11, the local frequency signal generator 1501 includes a VCO 1510 and a VCO 1
A frequency divider 1521 that divides a signal supplied from 510 and a frequency and a phase of an output of the frequency divider 1521 and a reference signal Sr supplied from an external reference frequency generator such as a crystal oscillator (not shown) are compared. A phase frequency comparator / charge pump 1522, an LPF 1523 that filters the output of the phase frequency comparator / charge pump 1522 and supplies the output to the VCO 1510, and an output buffer 1530, and further outputs the output of the frequency divider 1521 to the phase frequency comparator. A delay circuit 1541 is inserted in a circuit that is supplied to one input terminal of the charger / charge pump 1522.

In the local frequency signal generation unit 1501 of FIG. 11, the delay time in the delay circuit 1541 is adjusted by the control signal Sc3 supplied from the above-described control unit 230 of the baseband signal processing unit 200, whereby the RF signal processing unit 100 ( The timing of turning on (operating) the corresponding part) is controlled.
FIG. 12 is a block diagram showing another configuration example for controlling the timing for turning on (operating) the RF signal processing unit 100 (or its corresponding part). This timing control is performed by controlling the oscillation operation of the above-described PLL local frequency signal generation unit 1500. Also in FIG. 12, the corresponding parts to those in FIG. It is shown with a reference numeral.

In FIG. 12, the local frequency signal generator 1502 includes a VCO 1510 and a VCO 1
A frequency divider 1521 that divides a signal supplied from 510 and a frequency and a phase of an output of the frequency divider 1521 and a reference signal Sr supplied from an external reference frequency generator such as a crystal oscillator (not shown) are compared. A phase frequency comparator / charge pump 1522, an LPF 1523 that filters the output of the phase frequency comparator / charge pump 1522 and supplies the output to the VCO 1510, and an output buffer 1530. Further, the reference frequency Sr is converted into the phase frequency comparator. A delay circuit 1542 is inserted in a circuit supplied to the reference signal input terminal of the charge pump 1522.
In the local frequency signal generation unit 1502 in FIG. 12, the delay time in the delay circuit 1542 is adjusted by the control signal Sc4 supplied from the above-described control unit 230 of the baseband signal processing unit 200, whereby the RF signal processing unit 100 ( The timing of turning on (operating) the corresponding part) is controlled.

(Fifth embodiment)
FIG. 13 is a block diagram showing a receiving apparatus 15 as a fifth example of the present invention, which is a more specific form of the above-described embodiment. 5 corresponding to those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
In the embodiment of FIG. 13, in the other embodiment described above, the control unit provided in the baseband signal processing unit 200 includes a RF signal processing unit 100 and a baseband signal processing unit 201. One functional unit 3 in the system controller 300 for overall management of the entire system
10 is set.
In this way, the control unit 310 is configured as one function unit in the system controller 300 that comprehensively manages the entire system of the receiving device 15 including the RF signal processing unit 100 and the baseband signal processing unit 201. According to this, more sophisticated control becomes possible.

(Sixth embodiment)
As described with reference to FIG. 13, the control unit controls the RF signal processing unit 100 and the baseband signal processing unit 200 in an integrated manner independently of the RF signal processing unit 100 and the baseband signal processing unit 200. When the system controller 300 is provided, the system controller 300 can be configured to control the operation and non-operation of the baseband signal processing unit 200.

That is, an RF signal processing unit 100 that receives a transmitted signal modulated by a predetermined modulation method and down-converts the received signal, and a modulation for each symbol period of the signal down-converted by the RF signal processing unit 100 A baseband signal processing unit 200 that demodulates digital data based on the state and a control unit 300 as described above, and a receiver 15 for a transmitted signal
The baseband signal processing unit 200 is operated intermittently by limiting to a predetermined partial period in each symbol period of the transmitted signal modulated by the control unit 300 by the control unit 300. Control.

In the embodiment in which the control unit 300 functions as described above, the baseband signal processing unit operates intermittently only in a predetermined partial period in each symbol period of the transmitted signal that has been modulated by the predetermined modulation method. Therefore, a signal (carrier phase modulation state) is detected for each partial period in each successive symbol period and the baseband signal is demodulated, while these partial periods in each successive symbol period Since the baseband signal processing unit is inactive during other periods, power consumption is significantly suppressed.

As can be easily understood from the description regarding the above-described embodiment, the present invention performs RF signal processing for receiving a transmitted signal that has been modulated by a predetermined modulation method and down-converting the received signal. It is also summarized as a technical idea of a receiving method characterized in that it is executed intermittently limited to a predetermined partial period in each symbol period of a transmitted signal modulated by a predetermined modulation method.

In this receiving method, a signal (phase modulation state of a carrier wave) is detected for each partial period in each successive symbol period and a baseband signal is demodulated, while other than these partial periods in each successive symbol period During this period, since the RF signal processing is suspended, the power consumption is greatly suppressed.
The present invention also provides digital data based on the state of modulation for each symbol period of a signal that is received by receiving a transmitted signal that has been modulated by a predetermined modulation method, and that has undergone RF signal processing on the received signal. Technical idea of a receiving method, wherein baseband signal processing for demodulating a signal is intermittently executed only in a predetermined partial period in each symbol period of a transmitted signal modulated by the predetermined modulation method Is also summarized.

In this receiving method, a signal (phase modulation state of a carrier wave) is detected for each partial period in each successive symbol period and a baseband signal is demodulated, while other than these partial periods in each successive symbol period Because baseband signal processing is paused during
Power consumption is greatly suppressed.
Overall, the following practical advantages are obtained when implementing the technique of the present invention.
That is, in general, in a wireless system, a VCO having a good phase noise characteristic such as an LC oscillator is required, and an external inductor or an on-chip inductor is required.
In the present invention, the RF signal processing unit 100 (or the corresponding part) only needs to be accurately turned on, and therefore, a phase noise characteristic such as a ring oscillator is inferior, but a circuit with a very small area can be applied.

The reason why the ON timing in the above is accurate is as follows. That is, in the case of an oscillator that is always operating, the frequency deviation and the phase deviation are added over time. Therefore, if the oscillator is operated for a long time (all sequential symbol periods), a deviation from the received signal occurs. This adversely affects BER.
On the other hand, in the present invention, since the operation of the RF signal processing unit 100 (or its corresponding part) is intermittent as described above and is turned off in a short time, the phase (frequency) of the received signal is increased by adding noise. The degree of deviation with respect to is reduced.

In the apparatus according to the conventional system, the influence of the above-described deviation appears remarkably particularly in a device having poor phase noise characteristics such as a ring oscillator.
In the case of a CDMA receiver effective by applying the present invention, a temperature-compensated crystal oscillator (TCXO) is generally applied as a reference oscillator, but the accuracy is as high as about ± 2.5 ppm. The on-timing will be synchronized to this very accurate TCXO, so very accurate control can be performed with respect to the on-timing point.

It is a wave form diagram showing the operation timing of the signal and apparatus for demonstrating the principle of this invention. It is a block diagram showing the receiver as one embodiment of this invention. It is a block diagram showing the receiver as a 1st Example of this invention. It is a block diagram showing the receiver as a 2nd Example of this invention. It is a block diagram showing the receiver as a 3rd Example of this invention. It is a block diagram showing the receiver as a 4th Example of this invention. It is a block diagram showing in more detail the structure of the local frequency signal generation part of the RF signal processing part in FIGS. FIG. 8 is a block diagram illustrating a configuration example of the VCO in FIG. 7. FIG. 8 is a block diagram illustrating another configuration example of the VCO in FIG. 7. It is a figure for demonstrating the mode of the adjustment of the timing which operates the whole RF signal processing part thru | or the applicable part in each Example. It is a block diagram showing one structural example for controlling the timing which turns on RF signal processing part or its applicable part. It is a block diagram showing the other structural example for controlling the timing which turns on RF signal processing part or its applicable part. It is a block diagram showing the receiver as a 5th Example of this invention. It is a wave form diagram showing the signal of the BPSK system which is one of the general phase modulation systems.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 11, 12, 13, 14, 15 ... Receiver 100 ... RF signal processing part 150 ... Local frequency signal generation part 151 ... VCO 152 ... Phase synchronization circuit 153 ... Buffer 200 ... Baseband signal processing part 230 ... Control part 300 ... System controller
310 ... Control unit

Claims (13)

An RF signal processing unit which receives a transmitted signal modulated by a predetermined modulation method and down-converts the received signal, and a modulation state for each symbol period of the signal down-converted by the RF signal processing unit A baseband signal processing unit for demodulating digital data, and a receiving device for a transmitted signal,
A control unit that controls the RF signal processing unit to operate intermittently limited to a predetermined partial period in each symbol period of the transmitted signal that has been modulated by the predetermined modulation method; A receiving device. The control unit selects a period including a central position in each symbol period as the predetermined partial period in each symbol period of a transmitted signal modulated by the predetermined modulation method. Item 4. The receiving device according to Item 1. The baseband signal processing unit detects the signal quality received by the RF signal processing unit, and the control unit operates the RF signal processing unit intermittently according to the detected quality value. The receiving apparatus according to claim 1, wherein the receiving apparatus is controlled. The RF signal processing unit includes a PLL-based local frequency signal generation unit configured to include a voltage-controlled oscillation circuit, a phase synchronization circuit, and a buffer, and generate a local frequency signal, and
The receiving apparatus according to claim 1, wherein the control unit controls the voltage-controlled oscillation circuit of the local frequency signal generation unit to operate intermittently. The RF signal processing unit includes a PLL-based local frequency signal generation unit configured to include a voltage-controlled oscillation circuit, a phase synchronization circuit, and a buffer, and generate a local frequency signal, and
The receiving apparatus according to any one of claims 1 to 3, wherein the control unit controls the buffer of the local frequency signal generation unit to operate intermittently. The RF signal processing unit includes a voltage-controlled oscillation circuit, a phase synchronization circuit, and a buffer, and includes a PLL local frequency signal generation unit that generates a local frequency signal, and
4. The control unit according to claim 1, wherein the control unit controls the entire local frequency signal generation unit including a voltage controlled oscillation circuit, a phase synchronization circuit, and a buffer to operate intermittently. The receiving device described in 1. The receiving apparatus according to claim 1, wherein the control unit performs control so that the entire RF signal processing unit is operated intermittently. The receiving apparatus according to claim 1, wherein the control unit is provided in the baseband signal processing unit. The control unit is set as one function unit in a system controller that comprehensively manages the entire system of a receiving apparatus including the RF signal processing unit and the baseband signal processing unit. Item 8. The receiving device according to any one of Items 1 to 7. An RF signal processing unit which receives a transmitted signal modulated by a predetermined modulation method and down-converts the received signal, and a modulation state for each symbol period of the signal down-converted by the RF signal processing unit A baseband signal processing unit for demodulating digital data, and a receiving device for a transmitted signal,
A control unit for controlling the baseband signal processing unit to operate intermittently limited to a predetermined partial period in each symbol period of the transmitted signal modulated by the predetermined modulation method; A receiving device. The control unit is set as one function unit in a system controller that comprehensively manages the entire system of a receiving apparatus including the RF signal processing unit and the baseband signal processing unit. Item 11. The receiving device according to Item 10. RF signal processing for receiving a transmitted signal modulated by a predetermined modulation method and down-converting the received signal is performed for a predetermined partial period in each symbol period of the transmitted signal modulated by the predetermined modulation method. A receiving method characterized by being intermittently executed for a limited period. A baseband signal that receives a transmitted signal modulated by a predetermined modulation scheme, demodulates digital data based on a modulation state for each symbol period of the down-converted signal by performing RF signal processing on the received signal A receiving method, wherein the process is intermittently executed by limiting to a predetermined partial period in each symbol period of a transmitted signal that has been modulated by the predetermined modulation method.

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