JP3389153B2 - Diversity control device for mobile phone and diversity control method therefor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diversity control device for a mobile telephone suitable for reception in a mobile telephone in a mobile communication system according to a radio environment and a diversity control method therefor.

[0002]

2. Description of the Related Art In a mobile phone in a mobile communication system, the reception characteristics are deteriorated when the radio wave environment is bad such as a weak electric field or a fading environment, and communication is hindered.

In order to solve such a problem, there has been proposed a diversity system in which two systems of antennas are prepared and a signal received by the antenna having the better reception sensitivity of the two antenna outputs is demodulated.

[0004]

However, in the above-mentioned conventional diversity method, there is a problem that it is not possible to apply the synthetic diversity having an excellent diversity effect because the battery consumption is increased due to the increase in power consumption.

In addition, when the mobile station shifts to a peripheral base station due to deterioration of the radio wave environment, the shift process may fail due to the fact that an appropriate peripheral base station cannot be found. In this case, it is necessary to continue the communication on the original channel, but it may be difficult to restart the channel.

The present invention has been made in view of such a situation, and stabilizes the reception characteristics, reduces the power consumption,
An object of the present invention is to provide a diversity control device for a mobile phone and a diversity control method thereof that can facilitate restarting of a channel.

[0007]

According to a first aspect of the present invention, there is provided a diversity control device for a mobile phone, comprising: a plurality of antennas for receiving radio waves; an RF switch for switching the antennas; and a plurality of radio section receivers for wireless communication. A circuit, a phase detector provided corresponding to these radio section reception circuits, for detecting the instantaneous phase of the phase-modulated reception wave from each radio section reception circuit, and a phase detected by these phase detectors. A combining circuit for combining, a logic switch for switching between combining diversity and antenna selection switching diversity, and demodulation based on the detected phase value, and the phase value and logic
The demodulation logic circuit that outputs the reception quality determined by the degree of difference with the ideal value, the reception electric field detection circuit that measures the electric field strength of the received wave from the radio section reception circuit, and the measured electric field strength Based on the fading pitch detection circuit that detects the fading state of the received wave, a memory that stores a threshold value for determining either the combining diversity or the antenna selection switching diversity, and the combining diversity based on the threshold value. Alternatively, a diversity method determination unit that determines either antenna selection switching diversity and a power control unit that controls ON / OFF of the power supplied to each unit are provided.
The diversity method determination unit receives the signal output from the demodulation logic circuit.
Quality and electric field strength of the received wave output by the received electric field detection circuit
And the phasing output from the fading pitch detection circuit
The RF pitch is compared with the memory pitch and the memory threshold.
And divers for controlling the switching of logic switches
Output a locality method identification signal . In addition, the threshold stored in the memory is determined to be that the radio environment has deteriorated when any of the following factors occurs: low received electric field, large fading, poor reception quality, and combined diversity diversity. To switch to the antenna selection switching diversity by determining that the radio wave environment has improved when the factor disappears. Further, the logic switch can select whether to demodulate either the combined phase from the combining circuit or the non-combined phase of either one of the phase detectors based on the diversity system identification signal. Further, the power supply control unit, based on the diversity method identification signal, applies power to all the circuits in the case of combining diversity to turn it on, and in the case of antenna selection switching diversity, the radio unit receiving circuit, the phase detector and the combining circuit The power can be turned off. Further, the RF switch can be incorporated in the radio receiving circuit. Further, the threshold value of the memory can be updated to a value suitable for the environment by estimating the transition of the radio wave environment based on the accumulation of the determination result by the diversity method determination unit. The method of controlling diversity of a mobile phone according to claim 7 , wherein a first step of receiving radio waves by a plurality of antennas, a second step of switching the antennas by an RF switch, and a plurality of wireless section receiving circuits are used for wireless communication. A third step to be performed, a fourth step corresponding to these radio section receiving circuits, in which the instantaneous phase of the phase-modulated received wave from each radio section receiving circuit is detected by a phase detector, and these phase detectors The fifth step of synthesizing the detected phases by the synthesizing circuit, the sixth step of switching the synthesizing diversity and the antenna selection switching diversity by the logic switch, and the demodulation by the demodulating logic circuit based on the detected phase value. Doing and phase
The received quality determined by the degree of difference between the value and the ideal value is output.
The seventh step of force, an eighth step of measuring the received field detecting circuit the electric field intensity of a received wave from the radio unit receiving circuit on the basis of the measured field strength, the fading pitch detecting fading conditions of the received wave A ninth step of detecting by the circuit, a tenth step of storing a threshold value for determining either the combined diversity or the antenna selection switching diversity, and the combined diversity or the antenna selection switching diversity based on the threshold value. 11th step of determining any of the above, and a 12th step of performing on / off control of power supply to each unit, and the 11th step includes
Reception quality output from demodulation logic circuit and reception electric field detection circuit
The electric field strength of the received wave output by the
The fading pitch output by the output circuit and the threshold of the memory
And the RF switch according to the comparison result.
And a diver for controlling the switching of logic switches
And a step of outputting a citizen identification signal . Further, in the tenth step, it is determined that the radio wave environment is deteriorated when any of the factors of low reception electric field, large fading, and poor reception quality occurs, and switching to the combining diversity is performed. Include a step of storing a threshold value and a step of storing a threshold value for judging that the radio wave environment has become good when the factor disappears and switching back to the antenna selection switching diversity. You can Further, the sixth step includes a step of selecting which of the combined phase from the combining circuit or the non-combined phase of either one of the phase detectors is demodulated based on the diversity method identification signal. be able to. In the twelfth step, based on the diversity system identification signal, in the case of combined diversity, power is supplied to all circuits to turn them on, and in the case of antenna selection switching diversity, the radio section reception circuit and phase detector. And disconnecting the power supply to the synthesis circuit. In addition, in the tenth step, a step of estimating the transition of the radio wave environment based on the accumulation of the determination result every time when either the composite diversity or the antenna selection switching diversity is determined, and the threshold value according to the estimation result are set. , And a step of updating to a value according to the environment. In the diversity control device for a mobile phone and the diversity control method therefor according to the present invention, the diversity determination section allows the reception quality output by the demodulation logic circuit, the reception field strength output by the reception field detection circuit, and the fading pitch detection circuit. The fading pitch to be output is compared with the threshold value of the memory to control the switching operation of the RF switch and the logic switch, and in the case of the combined diversity, the power is supplied to all the circuits and turned on. In the case of the antenna selection switching diversity, the power supply to the radio section receiving circuit, the phase detector and the combining circuit is turned off.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 is a block diagram showing an embodiment of a diversity control device for a mobile phone according to the present invention.

The diversity control device for a mobile phone shown in FIG. 1 (hereinafter referred to simply as "diversity control device") comprises antennas 1 and 2, an RF switch 3, a radio section receiving circuit 4 and the like.
5, phase detectors 6, 7, combining circuit 8, logical switch 9,
A demodulation logic circuit 10, a received electric field detection circuit 11, a fading pitch detection circuit 12, a memory 13, a diversity determination unit 14 and a power supply control unit 15 are provided.

The antennas 1 and 2 take in radio waves. The RF switch 3 performs a switching operation according to each of the composite diversity and the antenna selection diversity. That is, in the case of combined diversity, the radio waves arriving at the antennas 1 and 2 are input to the radio receiving circuits 4 and 5. In the case of antenna selection diversity, either one of the radio waves arriving at the antennas 1 and 2 is input to the radio section reception circuit 4 and is not input to the radio section reception circuit 5.

The radio section receiving circuits 4 and 5 are provided with an RF switch 3.
Captures radio waves that pass through. The phase detectors 6 and 7 detect the phases of the reception modulated waves received by the radio section reception circuits 4 and 5. The synthesizing circuit 8 synthesizes the detected phase values.

The logic switch 9 selects whether to demodulate the composite phase or the non-composite phase. Here, the operation logic of the logic switch 9 is demodulated using the phase value output by the combining circuit 8 in the case of combined diversity, and demodulated using the phase value output by the phase detector 6 in the case of antenna selection diversity. To do.

The demodulation logic circuit 10 demodulates the phase value on the selected side. The reception electric field detection circuit 11 detects the reception electric field strength. The fading pitch detection circuit 12 detects a fading pitch.

The memory 13 stores a judgment threshold value. This judgment threshold value is used to judge that the radio environment has deteriorated when any of the following factors occur: low received electric field, large fading, poor reception quality, and switching to combined diversity. And that for switching back to antenna selection switching by determining that the radio wave environment has become good when the factor disappears.

The diversity determination section 14 receives the reception quality output from the demodulation logic circuit 10, the received electric field strength output from the received electric field detection circuit 11, and the fading pitch detection circuit 1.
2 compares the fading pitch output by 2 with the determination threshold value of the memory 13, and outputs the diversity system identification signal 16
Is output. The diversity system identification signal 16 controls the RF switch 3 and the logic switch 9 described above.

In the case of the combining diversity, the power supply control unit 15 supplies power to all the circuits to turn it on, and in the case of the antenna selection switching diversity, the power supply to the radio unit receiving circuit 5, the phase detector 7 and the combining circuit 8 is supplied. Turn off by turning off. This reduces power consumption.

Next, the operation of the diversity control device having such a configuration will be described.

First, as the reception electric field strength detected by the reception electric field detection circuit 11, the reception electric field level output from the radio section reception circuits 4 and 5 is used.

In this case, in the case of the antenna selection switching diversity, the electric field strength corresponding to the selected antenna 1 or 2 is output. In the case of combining diversity, the maximum electric field strength in each receiving system or the average receiving electric field strength in each receiving system is output according to the standard of the combining circuit 8 to be used.

Next, the fading pitch detection circuit 12
Thus, the fading pitch is detected from the reception electric field level output by the reception electric field detection circuit 11. This fading pitch is the deviation of the reception electric field level output by the reception electric field detection circuit 11 within the own station slot.

The reception quality is determined by the demodulation logic circuit 10 based on the degree of difference between the input phase value and the ideal value.

The received electric field level, fading pitch and received quality thus obtained are input to the diversity determination section 14. The determination by the diversity determination unit 14 is performed by software processing. As a result, the degree of freedom is given to the determination when comparing with the threshold value after the time average, the number of times average, and the instantaneous value are obtained from each input detection element.

Then, the diversity determination unit 14
It is determined whether the combining diversity or the antenna selection switching diversity is appropriate. The determination result is output to the RF switch 3, the logic switch 9 and the power supply controller 15 as the diversity method identification signal 16.

In the case of combined diversity, the RF switch 3 inputs the radio waves arriving at the antennas 1 and 2 to the respective radio section reception circuits 4 and 5 based on the diversity method identification signal 16. In the case of antenna selection diversity, one of the radio waves arriving at the antennas 1 and 2 is received by the radio receiving circuit 4
Input to the radio section receiving circuit 5 and not to the radio section receiving circuit 5.

The logic switch 9 selects either the combined phase of the combining circuit 8 or the non-combined phase of the phase detector 6 based on the diversity system identification signal 16.

In the case of combined diversity, the power supply controller 15 supplies power to all circuits to turn them on based on the diversity method identification signal 16. Further, in the case of antenna selection switching diversity, the power supply control unit 15 turns off by cutting off the power supply to the radio unit reception circuit 5, the phase detector 7, and the synthesis circuit 8. This reduces power consumption.

As described above, in the present embodiment, the diversity determination unit 14 outputs the reception quality output from the demodulation logic circuit 10, the reception electric field strength output from the reception electric field detection circuit 11, and the fading pitch detection circuit 12. Since the fading pitch to be controlled is compared with the threshold value of the memory 13 to control the switching operation of the RF switch 3 and the logic switch 9, stabilization of the reception characteristic and facilitation of channel restart are achieved. be able to.

Further, in the present embodiment, the power supply controller 15
Therefore, in the case of the combining diversity, all the circuits are powered on and turned on, and in the case of the antenna selection switching diversity, the power supply to the radio receiving circuit 5, the phase detector 7 and the combining circuit 8 is cut off. It is possible to reduce power consumption.

Further, in the present embodiment, since the received electric field strength, fading pitch, and received quality are used together as the criterion for switching the diversity system, it is possible to estimate the radio wave environment from various viewpoints, and it is accurate. It becomes possible to make a judgment.

Furthermore, since the subsequent processing to the peripheral base station can be performed from an early stage, stable reception can be performed until the transfer is completed. Therefore, when transferring to the peripheral base station, the original channel fails and the original channel is restored. It is possible to prevent the interruption of the call due to a failure in restarting.

In the present embodiment, the case where the receiving system is set to two has been described, but the present invention is not limited to this example, and as shown in FIG. 2, for example, the antenna 17, the radio section receiving circuit 18, and the phase detector. It is also possible to have three lines with 19 added.

The present invention is not limited to this example, and the number of receiving systems may be four or more. Further, the receiving system may be one system. In this case, a plurality of antennas are provided, and analog synthesis is performed immediately after input from each antenna, whereby the same function as described above can be achieved.

Further, the case where the RF switch 3 is arranged in the preceding stage of the radio section reception circuits 4 and 5 has been described, but the present invention is not limited to this example, and the RF switch 3 is arranged to the radio section reception circuits 4 and 5.
It can be built in.

That is, as shown in FIG. 3, the radio section receiving circuits 4 and 5 are provided with a BPF (band pass filter) 4
a, 5a, RF (high frequency) amplifiers 4b, 5b, MIX
(Mixers) 4c and 5c and BPFs (band pass filters) 4d and 5d are provided. Then, the RF switch 3 is arranged at the subsequent stage of the RF amplifiers 4b and 5b.

Further, as a method of diversity determination, there can be used a method of averaging by dividing into time and number of sections and clearing the arithmetic register each time the averaging of each section is completed. It is also possible to use a method of clearing the arithmetic register every time the judgment is changed. It is also possible to use a method in which the CPU load is saved by not normally performing calculations, and the average calculation is performed after any of the determination factors exceeds the threshold value. It is also possible to use a method in which the diversity method is switched immediately when any of the judgment elements exceeds the threshold value.

Further, the threshold value of the memory 13 may be updated to a value suitable for the environment by estimating the transition of the radio wave environment based on the accumulation of the determination result by the diversity method determination unit 14. it can. As a result, it becomes possible to stabilize the reception characteristics according to changes in the radio wave environment, reduce power consumption, and facilitate channel restart.

[0038]

As described above, according to the diversity control device for a mobile phone and the diversity control method therefor according to the present invention, the diversity determination section causes the reception quality output by the demodulation logic circuit and the reception output by the reception electric field detection circuit. The electric field strength, the fading pitch output from the fading pitch detection circuit, and the threshold value of the memory are compared to obtain RF.
In addition to controlling the switching operation of the switch and the logic switch, the power supply control unit supplies power to all circuits to turn them on in the case of combining diversity, and in the case of antenna selection switching diversity, the radio receiving circuit, phase detector and combining Since the power supply to the circuit is cut off, it is possible to stabilize the reception characteristic, reduce the power consumption, and easily restart the channel.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a diversity control device for a mobile phone of the present invention.

FIG. 2 is a block diagram showing another embodiment in which the configuration of the diversity control device of the mobile phone of FIG. 1 is changed.

3 is a block diagram showing still another embodiment when the configuration of the diversity control device of the mobile phone of FIG. 1 is changed.

[Explanation of symbols]

1,2,17 antenna 3 RF switch 4, 5, 18 Radio receiver circuit 4a, 5a, 4d, 5d BPF 4b, 5b RF amplifier 4c, 5c MIX 6,7,19 Phase detector 8 Compositing circuit 9 Logical switch 10 Demodulation logic circuit 11 Received electric field detection circuit 12 Fading pitch detection circuit 13 memory 14 Diversity determination section 15 Power control unit 16 Diversity method identification signal

Continuation of the front page (56) Reference JP-A-60-100840 (JP, A) JP-A-1-149619 (JP, A) JP-A-2-288735 (JP, A) JP-A-3-253124 (JP , A) JP 6-303171 (JP, A) JP 7-15380 (JP, A) JP 9-321679 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB) Name) H04B 7/02-7/12 H04L 1/02-1/06

Claims (11)

(57) [Claims] 1. A plurality of antennas for receiving radio waves, an RF switch for switching the antennas, a plurality of radio section reception circuits for performing radio communication, and a plurality of radio section reception circuits provided corresponding to the radio section reception circuits. A phase detector that detects the instantaneous phase of the phase-modulated received wave from the radio receiving circuit, a combining circuit that combines the phases detected by these phase detectors, and a logic that switches between combining diversity and antenna selection switching diversity. A switch, and performs demodulation based on the detected phase value, and
Reception quality determined by the degree of difference between the phase value and the ideal value
A demodulation logic circuit that outputs, a reception electric field detection circuit that measures the electric field strength of the reception wave from the radio section reception circuit, and a fading pitch detection that detects the fading state of the reception wave based on the measured electric field strength. A circuit, a memory that stores a threshold value for determining either the synthetic diversity or the antenna selection switching diversity, and based on the threshold value, determines either the synthetic diversity or the antenna selection switching diversity. And a power supply control unit that controls ON / OFF of the power supplied to each unit , wherein the diversity system determination unit includes a reception quality output from the demodulation logic circuit and the reception electric field.
The electric field strength of the received wave output by the detection circuit and the phase
Fading pitch output by the pitching pitch detection circuit,
The RF switch is compared with a threshold value of the memory.
And diversity for controlling the switching of logical switches
A diversity control device for a mobile phone, which is characterized by outputting a check method identification signal . 2. The threshold value stored in the memory is determined to have deteriorated the radio wave environment when any of the factors of low received electric field, large fading, and poor reception quality occurs. And a switch for switching to the composite diversity and a switch for switching back to the antenna selection switching diversity when it is determined that the radio wave environment has become good when the factor disappears. 2. The diversity control device for a mobile phone according to 1. 3. The logic switch selects, based on the diversity system identification signal, whether to demodulate either the combined phase from the combining circuit or the non-combined phase of either one of the phase detectors. Claim 1 or 2
A diversity control device for a mobile phone as set forth in. 4. The power supply control unit applies power to all circuits to turn them on in the case of the composite diversity based on the diversity system identification signal, and turns on the radio unit reception circuit in the case of the antenna selection switching diversity, claims, characterized in that the cross power to the phase detector and combining circuit
Item 4. The diversity control device for a mobile phone according to any one of Items 1 to 3 . Wherein said RF switch, according to claim 1, characterized in that built into the radio unit receiving circuit
A diversity control device for a mobile phone according to any one of the above. 6. The threshold value of the memory is updated to a value suitable for the environment by estimating the transition of the radio wave environment based on the accumulation of the determination result by the diversity method determination unit. A diversity control device for a mobile phone according to claim 1 . 7. A first step of receiving radio waves by a plurality of antennas, a second step of switching the antennas by an RF switch, and a third step of performing wireless communication by a plurality of radio section receiving circuits, Corresponding to the radio section receiving circuit, the fourth step of detecting the instantaneous phase of the phase-modulated received wave from each radio section receiving circuit by the phase detector, and the phase detected by these phase detectors And a sixth step of switching the combining diversity and the antenna selection switching diversity by a logic switch, demodulating by a demodulation logic circuit based on the detected phase value, and the phase value Depending on the degree of difference from the ideal value
Based on the measured electric field strength, a seventh step of outputting the reception quality determined by the above, an eighth step of measuring the electric field strength of the received wave from the radio section reception circuit by the reception electric field detection circuit, A ninth step of detecting a fading state of the received wave by a fading pitch detection circuit, and a tenth step of storing a threshold value for determining either the combination diversity or the antenna selection switching diversity.
11th step of determining either the combining diversity or the antenna selection switching diversity based on the threshold value, and the 12th step of performing on / off control of the power supply to each unit.
And a step, wherein the eleventh step, the reception quality the demodulation logic circuit outputs, the received electric field
The electric field strength of the received wave output by the detection circuit and the phase
Fading pitch output by the pitching pitch detection circuit,
Comparing the threshold value of the memory with the RF switch and the logic switch according to the comparison result.
Diversity method identification signal for controlling switching
A method of controlling diversity in a mobile phone, comprising: 8. In the tenth step, the radio wave environment is determined to have deteriorated when any of the factors of low received electric field, large fading, and poor received quality occurs, and the combination is performed. A step of storing a threshold value for switching to diversity, and a step of storing a threshold value for switching back to the antenna selection switching diversity by determining that the radio environment has become good when the factor disappears. The diversity control method for a mobile phone according to claim 7 , which is included. 9. In the sixth step, which of the combined phase from the combining circuit and the non-combined phase of either one of the phase detectors is demodulated is selected based on the diversity method identification signal. Characterized by including steps
A diversity control method for a mobile phone according to claim 7 . 10. In the twelfth step, based on the diversity method identification signal, all the circuits are turned on by turning on the power in the case of the combined diversity, and the step of turning the circuits in the case of the antenna selection switching diversity is performed. The method for controlling diversity of a mobile phone according to any one of claims 7 to 9, further comprising a step of cutting off power to the radio section receiving circuit, the phase detector and the combining circuit. 11. The tenth step includes a step of estimating a transition of a radio wave environment based on an accumulation of determination results for each determination of either the combination diversity or the antenna selection switching diversity, and the estimation result. claims the threshold in response, characterized in that includes the step of updating the values appropriate to the environment
7. The diversity control method for a mobile phone according to any one of 7 to 10 .