JPH06224804A - Diversity receiver device - Google Patents

Abstract

PURPOSE:To reduce the power consumption of a diversity receiver used for a portable telephone set for example. CONSTITUTION:A diversity receiver device consists of the receivers 1a and 1n, a switch/detection means 3 which switches and detects in turn the receiving field output sent from the receivers 1a and 1n, and a changeover switch means 6. Furthermore an A/D converter means 4 and a storage/arithmetic means 5 are added to the diversity receiver device. The means 5 stores the input receiving field data in the corresponding storage area of a built-in storage part to produce and transmit a switch control signal through the mutual comparison of those field data. Then the means 5 transmits a power saving control signal to cut the supply of power to the unselected receivers as long as the average prescribed time of the receiving field data of the selected receiver is larger than the set threshold value, the fading frequency is lower than a prescribed level, and the receiving field data of the selected receiver is not reduced down to a set level or less compared with the precedent level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diversity receiver for mobile phones, for example. The diversity receiver for mobile phones is supposed to be used while being carried, so the power required for operation is supplied from the battery. However, the higher the power consumption of this device, the longer a call can be made with one charge. It shortens and gives the user an annoyance.

Therefore, it is necessary to reduce power consumption.

[0003]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional example. The operation of the figure will be described below. Since the # 1 receiver and # 2 receiver have the same configuration and the same function, the description will be given only for the former.

First, through the antenna 13a, for example, 800
The MHz band signal is input to the high frequency section 11a of the # 1 receiver 1a.
The high frequency section amplifies the input signal, frequency-converts it into a signal in the first intermediate frequency band, and sends it to the intermediate frequency section 12a.

The intermediate frequency section amplifies the input signal in the first intermediate frequency band, frequency-converts it into a signal in the second intermediate frequency band, demodulates it, and takes out the # 1 demodulated signal to change the switch.
In addition to being sent to 24, the # 1 received electric field output corresponding to the received electric field strength is sent to the changeover switch 21.

The # 2 receiver 1b also outputs the # 2 received electric field output and the # 2 demodulated signal to the changeover switches 21 and 24 in the same manner as described above.
By the way, the changeover switch 21 to which the changeover signal of the frequency f _s is applied alternately switches the # 1 received electric field output and the # 2 received electric field output, and sends them to the received electric field strength detector 22. The received electric field output is detected and sent to the sample hold 23.

The sample and hold 23 is composed of a sample and hold portion for # 1 receiver, a sample and hold portion for # 2 receiver, and a comparison portion, which are not shown. Therefore, the input detection voltage is sampled and held by the corresponding sample and hold section, then the two sample and hold voltages are compared by the comparison section, and the switching control signal that selects the demodulation signal of the receiver with the higher sample and hold voltage is switched. It is sent to the switch 24.

The changeover switch 24 sends, for example, the demodulated signal of the # 1 receiver as a demodulated output. In addition, changeover switch
The switching timing of 21 coincides with the timing of sample hold. Also, # 2 was not selected at this time
Power is still supplied to the receiver.

[0009]

SUMMARY OF THE INVENTION As described above, for example,
During the diversity operation, the mobile phone diversity receiver does not save the power of the receiver that does not select the demodulated signal, so that there is a problem that the time during which a call can be made by one charge is shortened.

An object of the present invention is to reduce power consumption.

[0011]

FIG. 1 is a block diagram showing the principle of the present invention. In the figure, 1a and 1n are a plurality of receivers that take out a demodulated signal from an input received signal and send out a received electric field output corresponding to the received electric field, and 3 sequentially switch the received electric field output sent by each receiver. Switching / detection means 6 for detecting by means of a switch switch means 6 for selecting and outputting a demodulation signal of the receiver having the maximum received electric field output among a plurality of received electric field outputs in response to the applied switching control signal. .

Reference numeral 4 is an analog / digital conversion means for converting the received electric field output sent by the switching / detection means into incoming electric field data, and 5 is a storage / control means. And the memory
The calculating means stores the received received electric field data in a corresponding storage area of the built-in storage portion, performs mutual comparison to generate / send the switching control signal, and stores the received electric field data of the selected receiver for a predetermined time. If the average value is higher than the set threshold value, the fading frequency is lower than the predetermined frequency, and the received electric field data of the receiver does not drop from the previous value to the set value or less, supply power to the unselected receiver. Send the power saving control signal to turn off.

[0013]

According to the present invention, the storage / calculation means generates and sends a switching control signal for selecting the demodulation signal of the receiver having the maximum received electric field output among the plurality of received electric field outputs.

The average value of the received electric field data of the selected receiver is equal to or higher than the set threshold value, the fading frequency is equal to or lower than the predetermined frequency, and the received electric field data of the receiver is equal to the previous value. If the value does not drop below the set value, a power saving control signal that cuts off the power supply to the receiver that is not selected is sent to save power in the diversity receiver.

If even one of the above conditions is not satisfied, fading cannot be followed and power saving is not performed.

[0016]

2 is a block diagram of an embodiment of the present invention, and FIG.
3A and 3B are explanatory diagrams of a memory / arithmetic portion in FIG. Further, FIG. 4 is a diagram for explaining the operation of FIG. 2, in which (a) is a case where the fading pitch is small (diversity mode), and (b) is a case where the fading pitch is large (power save mode).

Here, the changeover switch 31 and the reception electric field strength detector 32 are the constituent parts of the changeover / detection means 3, the CPU 51, and the ROM 5.
2, interfaces 53, 54 and RAM 55 represent the constituent parts of the storage / operation means 5.

The same reference numerals denote the same objects throughout the drawings. The operation of FIG. 2 will be described below with reference to FIGS. 3 and 4, assuming that there are two receivers # 1 receiver 1a and # 2 receiver 2a.
It should be noted that the parts described in detail above will be briefly described, and the parts of the present invention will be described in detail.

First, an 800 MHz band signal is input to the high frequency part 111a of the # 1 receiver 1a via the antenna ANT-1. The high frequency part is the first generated by amplifying and frequency converting the input signal
The signal in the intermediate frequency band is passed through the amplifier 112a to the mixer section 11
Add to 3a.

Since a local oscillator signal (not shown) is also added to the mixer portion 113a, after the frequency conversion of the signal in the first intermediate frequency band into the signal in the second intermediate frequency band, the amplification portion 121a,
The # 1 demodulated signal is taken out via the band pass filter 122a, the limiter 123a, and the detection section 124a and sent to the changeover switch 6. Further, similarly to the above, the mixer section sends the # 1 received electric field output to the changeover switch 31.

The # 2 receiver also sends the # 2 received electric field output and the demodulated signal to the changeover switch 31 and the changeover switch 6 in the same manner as described above. Since the changeover signal of the frequency f _s is applied to the changeover switch 31, this switch alternately outputs the # 1 received electric field output and the # 2 received electric field output to the received electric field strength detector 32.

Therefore, the received electric field strength detector 32 detects the received electric field output, converts it into digital data by the A / D converter 4, and sends it to the storage / operation means 5. The memory / arithmetic means has the structure shown in FIG. 3A, and the output of the A / D converter 4 in FIG. 2 is stored in the corresponding area of the RAM 55 via the interface 53. Since the ROM 52 stores a program for executing the flow chart shown in FIG. 3B, the CPU 51 determines whether the power save mode or the diversity mode is executed according to FIG. 3B.

In addition to this, as described in the conventional example, 2
A switching control signal for comparing the magnitudes of the received electric field outputs (digitalized in the embodiment) sent by two receivers and selecting the demodulated signal of the receiver that sent the larger received electric field output. A program for sending is also stored.

Next, the operation of the storage / calculation means is as follows. <In the case of diversity mode (see Fig. 4 (a)> Normally, when the car is running, for example, the fading frequency is about 50 Hz (the corresponding fading pitch is about 10 ms), but the fading pitch is small like this. Sometimes diversity mode is applied.

[0025] CPU 51 of FIG. 3 (a), # 1 is digitized to alternately input at the timing of the frequency f _s, compares the received field output # 2 receivers, the larger the received field output The changeover control signal is sent to the changeover switch 6 so as to take out the demodulated signal of the sent receiver (the same function as the conventional example), and the average value of the received electric field output, the fading frequency, and the previous value are shown according to the flowchart shown in FIG. 3 (b). The magnitude of the received electric field output and the predetermined value are sequentially compared (Fig. 4 (a)-
, See).

At this time, since the fading frequency has a large threshold value set, the power saving control signal is not sent to the receiver having the smaller received electric field, and the power is supplied as it is. The reason for this is that the fading frequency is high, so the switching of demodulated signals must be executed at high speed, but if the power is saved, the rise time of the receiver not selected will be delayed (
This is because it takes time for the local oscillation signal and the bias voltage to stabilize), and it is not possible to follow the high speed switching. <In power save mode (see Fig. 4 (a)>) While walking or when the car is stopped, for example, the fading frequency is 5
Although it is about Hz (fading pitch is about 10 ms),
In this way, when the fading pitch is large, the high speed switching is not performed and the power save mode is applied.

When the two received electric field outputs are in the area A of FIG. 4 (b)-, the CPU 51 of FIG. 3 (a) outputs the demodulated signal of the # 1 receiver which has transmitted the # 1 received electric field output. As well as sending the changeover control signal to the changeover switch, the power saving control signal is sent to the # 2 receiver because all the conditions shown in the flowchart of Fig. 3 (b) are satisfied, and the power to this receiver is sent. Turn off supply.

The CPU 51 continues to compare the magnitudes of the two received electric field outputs with each other and detects whether or not the conditions shown in the flowchart of FIG. 3B are satisfied, but at time A ₀ . # 1 Since it was detected that the received electric field output was lower than the previous value by a predetermined value or more, power was supplied to the # 2 receiver to switch to diversity mode (the shaded area in Figure 4 (b)- ).

Then, when the # 2 received electric field output also becomes larger than the # 1 received electric field output, a switching control signal for extracting the # 2 demodulated signal is sent out, and the flowchart of FIG. 3 (b) is executed again. If all the conditions shown are satisfied, a power saving control signal is sent to the # 1 receiver to perform power saving (see Fig. 4 (b)-,).

As a result, it is possible to reduce the power consumption of the diversity receiving device for mobile phones.

[0031]

As described in detail above, according to the present invention, there is an effect that power consumption can be reduced.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment of the present invention.

3A and 3B are explanatory diagrams of a storage / arithmetic unit in FIG. 2, where FIG. 3A is a configuration diagram and FIG. 3B is a flow chart.

FIG. 4 is an operation explanatory diagram of FIG. 2, where (a) is a case where the fading pitch is small (diversity mode), and (b) is a case where the fading pitch is large (power save mode).

FIG. 5 is a configuration diagram of a conventional example.

[Explanation of symbols]

1a, 1n receiver 3 switching / detection means 4 analog / digital conversion means 5 storage / operation means 6 changeover switch means

Continued Front Page (72) Minoru Sakata Minoru 1-2-2, Ichibancho, Aoba-ku, Sendai City, Miyagi Prefecture Fujitsu Tohoku Digital Technology Co., Ltd.

Claims (1)

[Claims] 1. A plurality of receiving antennas, and a plurality of receivers (1a, 1n) for extracting a demodulated signal from a received signal input through the corresponding receiving antennas and sending a received electric field output corresponding to the received electric field. , Switching / detection means (3) for sequentially switching and detecting the reception electric field output transmitted by each receiver, and the maximum reception electric field output among a plurality of reception electric field outputs corresponding to the switching control signal to be applied. In a diversity receiver having a changeover switch means (6) for selecting and outputting a demodulated signal of the receiver, an analog / digital conversion means (4) for converting the output of the changeover / detection means into received electric field data, Memories and calculation means
(5) is provided, the storage / calculation means stores the input received electric field data in the corresponding storage area of the built-in storage portion, performs mutual comparison to generate / send the switching control signal, and selects Unless the average value of the received electric field data of the receiver for a predetermined time is greater than or equal to the set threshold value, the fading frequency is less than or equal to the specified frequency, and the received electric field data of the receiver does not drop below the set value from the previous value. A diversity receiver characterized in that a power saving control signal for cutting off power supply to a receiver not selected is transmitted.