JP2005020407A - Diversity receiving system and receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diversity receiving system with high flexibility in design in a simple circuital constitution having a base band unit to which excessive loading is not applied, and to provide its receiving method. <P>SOLUTION: When a strobe signal is entered, a timing control unit 107 generates a timing signal for directing a receive level measuring unit 106 and an antenna selecting unit 108 respectively to carry out each prescribed signal process according to the number of inputs (count number of strobe signal). The generated timing signal is entered in the receive level measuring unit 106 and the antenna selecting unit 108 respectively at the time of the timing or at the time after a prescribed period from the timing as a bench mark, when a prescribed number of the strobe signals are entered in the timing control unit 107. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna-selective diversity receiving apparatus and a diversity receiving method that can be used for a mobile communication terminal device such as a mobile phone and a base station device that performs radio communication with the mobile communication terminal device.
[0002]
[Prior art]
Conventionally, in wireless communication, it is known that a wireless signal deteriorates due to the influence of fading, multipath, and the like while passing through a propagation path. As a technique for suppressing the deterioration of the radio signal due to fading, a plurality of antenna elements are provided, and an antenna element having good radio signal reception quality is selected from them, and the received signal is extracted from the selected antenna element. An antenna selection type diversity communication apparatus is known (see, for example, Patent Document 1).
[0003]
FIG. 4 is a block diagram schematically showing a general configuration of the antenna selection type diversity communication apparatus. The diversity communication device 10 includes antenna elements 11 and 12, an antenna switch 13, an antenna sharing unit 14, a reception unit 15, a reception level measurement unit 16, an antenna selection unit 18, and a transmission unit 19. . In addition, the receiving unit 15 includes an AGC (Automatic Gain Control) unit 15a that amplifies the received signal with a predetermined amplification factor (gain value). In FIG. 4, for simplification, two antenna elements are provided with a minimum configuration, and components such as an amplifier and a filter that are not directly involved in the selection of the antenna elements are omitted. In order to perform diversity by selecting an antenna element, the time for measuring the reception level for each antenna element, the time for determining the reception quality by comparing this reception level for each antenna element, and the antenna element It takes time to switch.
[0004]
A reception signal received by the antenna element 11 or the antenna element 12 is input to the receiving unit 15 via the antenna switch 13 and the antenna sharing unit 14. In the receiving unit 15, the received signal is amplified by the AGC unit and then subjected to known signal processing such as A / D conversion and demodulation processing to be converted into received data. The received data is input to a baseband unit (not shown). On the other hand, the reception signal amplified by the AGC unit 15a is input to the reception level measurement unit 16, where the reception level is measured for each antenna element. The reception level measured for each antenna element is input to the antenna selection unit 18 where the antenna element with the higher reception quality, that is, the higher reception level is selected. Then, a switch switching signal is input from the antenna selection unit 18 to the antenna switch 13 so that the reception signal is input to the reception unit 15 from the selected antenna element.
[0005]
Here, in the baseband unit (not shown), when the reception data is input, an AGC control signal that is a command to the reception unit 15 is generated, and the operation timing is notified to the reception level measurement unit 16 or the antenna selection unit 18. Each timing signal is generated. Then, an AGC control signal is input from the baseband unit to the receiving unit 15, and a timing signal is input to the reception level measuring unit 16 and the antenna selecting unit 18 at a predetermined timing, and a predetermined function is exhibited in each component unit. The
[0006]
According to such an antenna selection type diversity communication device, an antenna element having a good radio wave propagation environment is adaptively selected from a plurality of antenna element groups, and a reception signal is extracted from the selected antenna element. The signal can always be kept above a certain quality.
[0007]
[Patent Document 1]
JP-A-1-189248
[0008]
[Problems to be solved by the invention]
However, the diversity communication device 10 described in FIG. 4 has the following problems. That is, in the diversity communication device 10, since the baseband unit collectively controls the operation of each component unit for selecting an antenna element having good reception quality of the received signal, the control signal in the baseband unit and each component unit is controlled. The circuit configuration becomes complicated, such as an increase in terminals. In addition, the baseband unit must generate and output an AGC control signal and timing signal in consideration of the signal processing speed of each component, and the signal processing in the baseband unit is complicated and its load is large. Furthermore, since the wiring for connecting the reception unit 15, the reception level measurement unit 16, the antenna selection unit 18, and the baseband unit is complicated, it is difficult to divide these into separate units. The degree of freedom of 10 designs is reduced.
[0009]
The present invention has been made in view of the above points, and an object of the present invention is to provide a diversity receiver having a simple circuit configuration, an excessive load on a baseband unit, and a high degree of design freedom, and a reception method thereof. And
[0010]
[Means for Solving the Problems]
A diversity receiving apparatus according to the present invention measures a plurality of antenna elements that receive radio signals, an antenna switch that switches the antenna elements that extract received signals, and a reception level of the extracted received signals for each antenna element. A reception level measuring means; an antenna selecting means for selecting the antenna element from which the reception signal is extracted by comparing the measured reception level for each antenna element; and an AGC control signal generated according to the reception signal. And a timing control means for controlling the timing at which the antenna selection means selects the antenna element.
[0011]
According to this configuration, there is provided a circuit configuration that does not require a direct instruction signal from the baseband unit and can autonomously determine an antenna element with good reception quality of the reception signal based on the existing AGC control signal. It is possible to reduce the load on the baseband unit, simplify the configuration of the diversity receiver, and increase the degree of design freedom.
[0012]
In the diversity receiver according to the present invention, in the above invention, the timing control unit is configured to control a timing at which the antenna selection unit selects the antenna element by counting a strobe signal included in the AGC control signal. take.
[0013]
According to this configuration, in addition to the effect of the present invention, the timing control unit only has to passively wait for the input strobe signal and count the number of inputs. The load can be reduced, and as a result, the time lag from when the strobe signal is input until the antenna element is selected by the antenna selection means can be reduced.
[0014]
The diversity receiver according to the present invention comprises AGC means for amplifying the received signal based on a gain value adjusted by the AGC control signal in the invention, and the timing control means is based on the AGC control signal. The gain value determining means for calculating the gain value in the AGC means and determining whether or not the antenna selecting means selects the antenna element based on the calculated gain value is adopted.
[0015]
According to this configuration, in addition to the effect of the present invention, it is only necessary to select an antenna element when the gain value in the AGC means is large, that is, when the reception level of the reception signal is small. While this is the case, the time for measuring the reception level for each antenna element, the time for determining the reception quality by comparing this reception level for each antenna element, and the time for switching the antenna element become unnecessary. Since all of these times can be used for extracting the received signal, the information transmission rate can be increased without degrading the reception quality of the received signal.
[0016]
The diversity reception method according to the present invention includes an antenna switch step for switching an antenna element from which a reception signal is extracted, a reception level measurement step for measuring the reception level of the extracted reception signal for each antenna element, and the measured reception An antenna selection step for selecting the antenna element for extracting the reception signal by comparing the level for each antenna element, an AGC control signal generation step for generating an AGC control signal according to the reception signal, and the generated And a timing control step for controlling the timing for selecting the antenna element in the antenna selection step based on an AGC control signal.
[0017]
According to this method, a direct instruction signal from the baseband unit is not required, and an antenna element with good reception quality of the received signal is determined autonomously by a circuit configuration that does not include the baseband unit based on the AGC control signal. Therefore, the load applied to the baseband unit can be reduced, the configuration of the diversity receiver can be simplified, and the degree of design freedom can be increased.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The essence of the present invention is that a reception unit that does not include a baseband unit based on an AGC control signal generated according to the reception level of the reception signal does not require a timing signal other than the AGC control signal. It is to independently select an antenna element having good reception quality.
[0019]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0020]
(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a diversity communication apparatus 100 using the antenna selection type diversity receiving apparatus according to Embodiment 1 of the present invention. Here, the diversity receiving device is a diversity communication device excluding the components used only for signal transmission, that is, the transmitting unit 109 in FIG.
[0021]
Diversity communication apparatus 100 includes antenna elements 101 and 102, antenna switch 103, antenna sharing unit 104, reception unit 105, reception level measurement unit 106, timing control unit 107, antenna selection unit 108, and transmission unit. 109. The receiving unit 105 includes an AGC unit 105a that amplifies the received signal with a predetermined gain value. Note that in this embodiment, the antenna element has two minimum elements.
[0022]
A radio signal received by the antenna element 101 or the antenna element 102 is input to the antenna switch 103. In the antenna switch 103, a received signal is taken out from the antenna element connected to the terminal of the closed circuit. The extracted received signal is input to the receiving unit 105 via the antenna sharing unit 104. In the receiving unit 105, the input received signal is amplified with a predetermined gain value by the AGC unit 105a mounted therein. This gain value will be described later. On the other hand, the amplified reception signal is input to reception level measuring section 106, where the reception level is measured. On the other hand, the amplified reception signal is subjected to predetermined signal processing such as A / D conversion and demodulation in the reception unit 105 and converted into reception data, and then input to a baseband unit (not shown).
[0023]
In a baseband unit (not shown), when reception data is input, an AGC control signal corresponding to the reception level is generated. Here, the AGC control signal is composed of three signals: a clock signal, a gain value adjustment signal, and a strobe signal. The clock signal is a signal for providing signal processing timing to the receiving unit 105, the gain value adjustment signal is a signal literally instructing the AGC unit 105a to increase or decrease the gain value, and the strobe signal is the gain of the gain signal. This is a pulse signal for informing the end of the value adjustment signal. Further, the gain value adjustment signal indicates that the gain value of the AGC unit 105a is lowered if the reception level of the reception data input to the baseband unit is higher than a preset value, while the reception is the same. If the level is lower than the set value, it is instructed to increase the gain value. Each signal constituting the AGC control signal is input to the receiving unit 105, but the strobe signal is branched before being input to the receiving unit 105 and input to the timing control unit 107.
[0024]
When the gain value adjustment signal is input to the receiving unit 105, the AGC unit 105a increases or decreases the gain value according to the instruction content of the gain value adjustment signal. In the AGC unit 105a, once the gain value is adjusted, the adjusted gain value is maintained until the next gain value adjustment signal is input.
[0025]
When the strobe signal is input to the timing control unit 107, the timing of the content instructing the reception level measurement unit 106 and the antenna selection unit 108 to perform predetermined signal processing according to the number of times of input (strobe signal count number). A signal is generated. Then, the generated timing signal is received from the reception level measurement unit 106, the antenna selection unit 108, and the timing control unit 107 at or after a predetermined period with reference to the timing at which a predetermined number of strobe signals are input. Respectively.
[0026]
The reception level measurement unit 106 measures the reception level of the amplified reception signal input from the reception unit 105 by envelope detection or the like for each antenna element, and receives the reception level as the measurement result from the timing control unit 107. The signal is input to the antenna selection unit 108 at the timing when the signal is input.
[0027]
The antenna selection unit 108 holds the reception level input from the reception level measurement unit 106 for a predetermined period. In addition, when a timing signal is input from the timing control unit 107, the antenna selection unit 108 compares the reception level for the antenna element 101 with the reception level for the antenna element 102, and the antenna having the higher reception level is compared. An element is selected. Then, a switch switching signal is input from the antenna selection unit 108 to the antenna switch 103 so that a reception signal is extracted from the selected antenna element.
[0028]
In the antenna switch 103, the switch is switched according to the input switch switching signal, and the received signal is continuously extracted from the same antenna element until the next switch switching signal is input.
[0029]
Transmission data is input to the transmission unit 109 from the baseband unit. The transmission data is subjected to known signal processing such as modulation and D / A conversion in the transmission unit 109 and converted into a transmission signal, and then transmitted by the antenna selection unit 108 via the antenna sharing unit 104 and the antenna switch 103. Radio transmission is performed from the selected antenna element.
[0030]
Next, the operation of the diversity receiver according to the present embodiment will be specifically described with reference to FIG. FIG. 2 is a diagram illustrating signal processing timing in each component of the diversity receiver according to the present embodiment.
[0031]
First, in the diversity receiver according to the present embodiment, in order to stabilize the reception level of a received signal when starting to receive a radio signal, a high-speed AGC section is allocated for a certain period from the start of reception. In this high-speed AGC section, the antenna switch 103 is fixed, and the reception signal is continuously input from the antenna element 101 selected at the start of reception to the reception unit 105. In the high-speed AGC section, reception data generated by performing predetermined signal processing on the reception signal in the reception unit 105 is continuously input to the baseband unit. In the baseband unit, the reception level of the reception data input from the reception unit 105 is measured, and an AGC control signal is generated in a short cycle according to the reception level. The generated AGC control signal is input from the baseband unit to the receiving unit 105, and the strobe signal therein is also input to the timing control unit 107. In the high-speed AGC section, the AGC control signal is input to the receiving unit 105 ten times, and the gain value of the AGC unit 105a is adjusted each time. By repeatedly adjusting the gain value based on the AGC control signal, the gain value converges and stabilizes at the end of the high-speed AGC period.
[0032]
Here, the timing control unit 107 does not react at all to the 10th strobe signal after the start of reception in the high-speed AGC section. Then, the timing control unit 107 uses the timing at which the high-speed AGC period ends and shifts to the low-speed AGC period A, that is, the timing of the strobe signal count number 11, as a reference, and after a certain period has elapsed, the reception level measurement unit 106 and antenna selection unit 108 The timing signal is input to each.
[0033]
After the transition from the high speed AGC section to the low speed AGC section A, the low speed AGC section is divided every time the AGC control signal is input to the receiving unit 105, that is, every time the strobe signal count number in the timing control unit 107 increases. Accordingly, when the AGC control signal is input to the receiving unit 105 in the low-speed AGC period A, the low-speed AGC period B thereafter occurs, and when the AGC signal is input to the receiving unit 105 in the low-speed AGC period B, the low-speed AGC is thereafter input. It becomes section C.
[0034]
In the low-speed AGC section A, the reception level measurement unit 106 receives the antenna element 101 from the beginning of the same section (timing of the strobe signal count of 11 in FIG. 2) for a certain period (a period sufficiently shorter than the low-speed AGC section A). Level is measured. When this fixed period has elapsed, a timing signal is input from the timing control unit 107 to the reception level measurement unit 106 and the antenna selection unit 108 (the timing of TS1 in FIG. 2). When this timing signal is input to the antenna selection unit 108, a switch switching signal including a switch switching instruction is input from the antenna selection unit 108 to the antenna switch 103 in order to extract a reception signal from the antenna element 102. When a timing signal is input to the reception level measurement unit 106 at the timing of TS1, the reception level for the antenna element 101 is input from the reception level measurement unit 106 to the antenna selection unit 108. The reception level for the antenna element 101 is temporarily held in the antenna selection unit 108.
[0035]
After outputting the reception level for the antenna element 101, the reception level measurement unit 106 receives the reception signal from the antenna element 102 amplified by the AGC unit 105a. Then, during the period until the next timing signal is input from the timing control unit 107 (TS2 timing in FIG. 2), the reception level measurement unit 106 measures the reception level of the antenna element 102. Note that the timings of TS1 and TS2 are independently measured by the timing control unit 107 with reference to the timing of the strobe signal count of 11.
[0036]
When the timing of TS2 in FIG. 2 arrives, a timing signal is input from the timing control unit 107 to the reception level measurement unit 106 and the antenna selection unit 108, respectively. When this timing signal is input to the reception level measurement unit 106, the reception level for the antenna element 102 is input to the antenna selection unit 108. Then, when this timing signal is input from the timing control unit 107, the antenna selection unit 108 receives the received level for the antenna element 101 and the newly received reception level for the antenna element 102. The comparison is started. In this comparison in the antenna selection unit 108, the antenna element with the higher reception level is selected. In the low-speed AGC section A, the gain value of the AGC unit 105a is fixed even when the switch of the antenna switch 103 is switched at the timing of TS1, and therefore the comparison in the antenna selection unit 108 is performed from the reception level measurement unit 106. It is only necessary to simply compare the received reception level for each antenna element.
[0037]
The comparison in the antenna selection unit 108 ends in the antenna selection section in FIG. 2, and a switch switching signal is sent from the antenna selection unit 108 to the antenna switch 103 so that a reception signal is extracted from the selected antenna element at the same time. Entered. In the antenna switch 103, the switch is switched according to the switch switching signal. The antenna switch 103 is fixed and selected during a period from the timing when the switch is switched to the timing when the next AGC control signal is input to the receiving unit 105 (the timing of the strobe signal count of 12 in FIG. 2). Received signals are continuously extracted from the other antenna element.
[0038]
Also, the reception level of the received data is measured at the baseband portion immediately before the timing of transition from the low-speed AGC section A to the low-speed AGC section B, that is, the timing of the strobe signal count number 12 in FIG. A control signal is generated. The AGC control signal is input from the baseband unit to the receiving unit 105, and the AGC unit 105a mounted on the receiving unit 105 adjusts the gain value again according to the input gain value adjustment signal. Then, from the timing of the strobe signal count number 12, signal processing similar to the signal processing in each step of the low-speed AGC section A described above is started.
[0039]
Thus, according to the diversity receiver according to the present embodiment, since a certain period from the start of reception is allocated to the high-speed AGC section, until the low-speed AGC section from which actually necessary information is extracted arrives. The hunting of the gain value in the AGC unit 105a can be eliminated. Thereby, according to the diversity receiver according to the present embodiment, high reception quality can be obtained from the beginning when information is actually extracted.
[0040]
Further, according to the diversity receiver according to the present embodiment, the timing control unit 107 only needs to wait passively until the strobe signal is input, and only needs to count the number of inputs. The signal processing load on the timing control unit 107 can be reduced. Thereby, according to the diversity receiver according to the present embodiment, it is possible to reduce the time lag until the timing signal is input from timing control section 107 to reception level measurement section 106 and antenna selection section 108.
[0041]
Note that the diversity receiver according to the present embodiment may be modified or applied as follows.
[0042]
In the present embodiment, a case has been described in which the antenna element has two minimum configurations, but the present invention is not limited to this case, and depends on the strength and frequency of the radio wave used, the radio wave propagation environment, and the like. Thus, the number of antenna elements may be increased as appropriate. Note that when the number of antenna elements increases, the timing of TS1 and the like in the low-speed AGC section increases, but the essential operation of signal processing in the diversity receiver is the same.
[0043]
In the present embodiment, the case where the gain value of the AGC unit 105a is fixed in the low-speed AGC sections A, B, and C has been described. However, the present invention is not limited to this case. For example, the timing of TS1 AGC control signals are generated and held immediately before the baseband portion, and AGC control signals are similarly generated immediately before the timing of TS2, and these AGC control signals are compared in the antenna selection section in FIG. The baseband unit performs selection similar to the antenna element selection by the antenna selection unit 108, and inputs the AGC control signal corresponding to the antenna element selected by the baseband unit to the reception unit 105. Also good. In this way, the gain value of the AGC unit 105a can be made to correspond to the antenna element selected by the antenna selection unit 108 at the timing when the antenna selection section in FIG. 2 ends. As a result, in the low-speed AGC sections A, B, and C, the reception level of the reception data input from the reception unit 105 to the baseband unit can be made closer to the target value.
[0044]
Further, in the present embodiment, the antenna selection type diversity receiver and the communication device using the same have been described. However, the diversity communication device 100 is used in a mobile communication terminal device such as a mobile phone or a wireless LAN mobile terminal device. Or it can incorporate in the base station apparatus which communicates with such a mobile communication terminal device.
[0045]
(Embodiment 2)
Hereinafter, the diversity receiving apparatus according to the second embodiment of the present invention will be described with reference to the drawings as appropriate, but the same reference is made to the constituent elements that exhibit the same functions as the constituent elements shown in the first embodiment. The reference numerals are attached and explanations thereof are omitted.
[0046]
FIG. 3 is a block diagram showing a configuration of diversity communication apparatus 300 using the diversity reception apparatus according to Embodiment 2 of the present invention. Diversity communication apparatus 300 includes a timing control unit 307 in which gain value determination unit 307 a is mounted in place of timing control unit 107 in diversity communication apparatus 100.
[0047]
A gain value adjustment signal is also input to the timing control unit 307 along with the strobe signal in the AGC control signal generated in the baseband unit (not shown). The timing control unit 307 continues to calculate the gain value according to the gain value adjustment signal input from the start of reception (timing of the strobe signal count of 1 in FIG. 2). That is, the gain value determination unit 307a can constantly monitor the gain value of the AGC unit 105a. The gain value determination unit 307a then selects the reception level measurement unit 106 and the antenna selection from the timing control unit 307 until the calculated gain value exceeds a predetermined threshold value, that is, until the reception level of the reception data falls below a certain value. The output is controlled so that the timing signal is not input to the unit 108. Therefore, in the diversity receiver according to the present embodiment, the switch selection signal is not input from antenna selection unit 108 to antenna switch 103 unless the reception level of the received data is below a certain value.
[0048]
Therefore, according to the diversity receiver according to the present embodiment, as long as the reception level of the received signal is at a communicable level, the low-speed AGC sections A, B, and C are separated (the strobe signal count numbers 11, 12 in FIG. 2). 13), the antenna switching is not performed, so the time for measuring the reception level for each antenna element, which is necessary in the first embodiment, is compared with the reception level for each antenna element. It is possible to use all of the time for determining the signal and the time for switching the antenna element for extracting the received signal, and the information transmission speed can be increased.
[0049]
Further, in the present embodiment, the antenna selection type diversity receiver and the communication device using the same have been described. However, the diversity communication device 300 is used in a mobile communication terminal device such as a mobile phone or a wireless LAN mobile terminal device. Or it can incorporate in the base station apparatus which communicates with such a mobile communication terminal device.
[0050]
【The invention's effect】
As described above, according to the present invention, a circuit configuration that does not require a direct instruction signal from the baseband unit and can autonomously determine an antenna element with good reception quality of the reception signal based on the AGC control signal. Therefore, the load on the baseband unit can be reduced, the configuration of the diversity receiver can be simplified, and the degree of freedom in design can be increased.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a diversity communication apparatus according to Embodiment 1 of the present invention.
FIG. 2 is a diagram illustrating operation timing of each component of the diversity receiver according to the first embodiment.
FIG. 3 is a block diagram showing a configuration of a diversity communication apparatus according to Embodiment 2 of the present invention.
FIG. 4 is a block diagram showing a general configuration of a conventional antenna selection type diversity communication apparatus;
[Explanation of symbols]
100, 300 Diversity communication device
101, 102 Antenna element
103 Antenna switch
104 Antenna common part
105 Receiver
105a AGC Department
106 Reception level measurement unit
107, 307 Timing control unit
108 Antenna selector
109 Transmitter
307a Gain value determination unit

Claims (4)

A plurality of antenna elements for receiving radio signals;
An antenna switch for switching the antenna element for extracting a received signal;
A reception level measuring means for measuring the reception level of the extracted reception signal for each antenna element;
Antenna selection means for selecting the antenna element from which the received signal is extracted by comparing the measured reception level for each antenna element;
A diversity receiving apparatus comprising: timing control means for controlling timing at which the antenna selection means selects the antenna element with reference to an AGC control signal generated according to the received signal. The diversity receiving apparatus according to claim 1, wherein the timing control unit controls the timing at which the antenna selection unit selects the antenna element by counting a strobe signal included in the AGC control signal. AGC means for amplifying the received signal based on a gain value adjusted by the AGC control signal,
The timing control means calculates the gain value in the AGC means based on the AGC control signal, and determines whether to cause the antenna selection means to select the antenna element based on the calculated gain value The diversity receiver according to claim 1, further comprising a value determination unit. An antenna switch step for switching an antenna element for extracting a received signal;
A reception level measuring step of measuring the reception level of the extracted reception signal for each antenna element;
An antenna selection step of selecting the antenna element from which the received signal is extracted by comparing the measured reception level for each antenna element;
An AGC control signal generating step for generating an AGC control signal according to the received signal;
A diversity control method, comprising: a timing control step of controlling a timing of selecting the antenna element in the antenna selection step based on the generated AGC control signal.

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