JP2943885B2 - Diversity Reception System for Mobile Radio Station - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving system for a mobile radio station in a mobile radio system.

[0002]

2. Description of the Related Art In a portable mobile radio station (hereinafter, also referred to as a portable device) performing a conventional diversity reception system, in order to reduce the size and weight of the device, the transmission output is reduced as much as possible to reduce power consumption. As a matter of fact, whip-type antennas that are relatively easy to obtain with a high gain are often used as transmission antennas. When such a whip-type antenna is used as a transmission / reception antenna for a mobile radio station that performs a diversity reception method, the antenna gain is significantly higher when the antenna is housed in a housing compared to a reception-only antenna. May drop. In such a state, the receiver selects a reception-only antenna to perform diversity reception.

[0003]

As described above, when the reception-only antenna is selected, the mobile radio station can determine that the value of the reception level from the mobile radio base station is sufficiently within the service area. Despite this, the radio wave from the mobile radio station may not reach the base station because the gain of the transmitting antenna is low. Therefore, there is a disadvantage in that the transmission or the response signal is recycled, which results in an unnecessary high load on the entire system, and that the battery of the portable device is unnecessarily consumed, thereby shortening the usable time.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem when the transmission / reception antenna gain and the reception antenna gain become unbalanced for some reason when the mobile radio station uses the diversity reception system. It is an object of the present invention to provide a diversity reception control method that can be used.

[0005]

The above problems are solved by the means described in the claims. That is, according to the first aspect of the present invention, in a mobile radio station using a diversity reception system including a transmission / reception shared antenna and a reception only antenna, a reception electric field level at the transmission / reception shared antenna and a reception electric field level at the reception only antenna are monitored. Then, the average value of each of the two levels within a certain time is compared, the average value of the reception level at the shared antenna for transmission and reception is lower than the average value of the reception level of the reception only antenna by a predetermined value or more, and, If the absolute value of the reception level at the shared antenna is less than or equal to a certain value, stop diversity reception, switch to the reception method using only the shared antenna, and then, if the reception level exceeds a certain value, This is a diversity reception method for controlling the diversity reception method using the transmission / reception shared antenna and the reception-only antenna so as to restart.

According to a second aspect of the present invention, a mobile radio station using a diversity reception system including a transmission / reception shared antenna and a reception-only antenna must transmit a signal to a radio base station and receive an acknowledgment signal. In the case where the number of times that the confirmation signal cannot be received despite transmitting the signal to the radio base station exceeds a certain value N,
Monitor the reception level at the shared antenna, and if the received level is less than a certain value, stop diversity reception, switch to the receiving method using only the shared antenna, and then if the received level exceeds a certain value This is a diversity receiving method for controlling the diversity receiving method with the transmission / reception shared antenna and the reception-only antenna so as to restart.

[0007]

The main feature of the present invention is that, in a mobile radio station using the diversity reception system, when the gain of the transmission / reception antenna is significantly lower than that of the reception only antenna, the reception system uses only the transmission / reception antenna. In a conventional mobile radio station using only the diversity reception scheme, even when the gain of the transmitting / receiving antenna is lower than the gain of the receiving antenna, the receiving level of the receiving antenna satisfies a predetermined value. If it was, it was determined that it was in the service area. for that reason,
In some cases, the transmitted radio waves did not reach the radio base station.

In the present invention, when the gain of the dual-use antenna is significantly lower than that of the reception-only antenna for some reason, this is detected, and the reception system using only the dual-use antenna is detected. This is a difference between the present invention and the prior art in that when the transmission radio wave from the mobile radio station does not reach the radio base station, it can be determined that the radio wave is out of the service area.

[0009]

FIG. 1 is a diagram for explaining an example of an antenna configuration of a mobile radio station to which the present invention is applied. In the figure, the transmitting and receiving antenna 1 can easily obtain a transmitting antenna gain.
In addition, it is a whip antenna that can be stored and has excellent portability, and the reception-only antenna 2 is a built-in antenna that has excellent portability.

FIG. 2 is a block diagram showing a configuration of a mobile radio station for explaining a first embodiment of the present invention.
FIG. 4 is a flowchart showing the control, and FIG. 4 is a diagram showing the relationship between the reception level and the control of the diversity reception. Hereinafter, an embodiment corresponding to claim 1 will be described with reference to these drawings.

In FIG. 2, 1 is a transmission / reception shared antenna,
2 is a reception only antenna, 3 is a duplexer, 4 is a transmitter, 5,
Reference numeral 6 denotes a receiver, 7 denotes a selector, 8 denotes a comparator, and 9 denotes a control unit. In FIG. 2, L1 indicates the result of detection of the reception level of the transmission / reception shared antenna, and L2 indicates the result of detection of the reception level of the reception-only antenna. In comparator 8, L1,
The level of L2 is compared, and the selector 7 selects the demodulated output of the receiver having the higher level. L is compared by the comparator 8
Level Lou, which is determined to have a higher level among 1 and L2
t and the reception level L1 of the shared antenna for transmission and reception are averaged and compared at a certain time constant T, and the level difference Lout − L1 (L1 << L2) is a specified value ΔL having a certain value.
If L1 is equal to or less than a predetermined value Lth1 when the value exceeds L, the control unit 9 stops the diversity reception by fixing the selector 7 to the transmission / reception shared antenna side by the signal S on the control line, and receives only the transmission / reception shared antenna side. And Here, Lout , L1 represents an average value between T of Lout, L1. Thereafter, the average value of L1 for t seconds is equal to a certain specified value Lt.
If h2 is greater than h2, the control section 9 makes a decision, and causes the selector 7 to perform a selecting operation based on the output of the comparator 8 by the signal S on the control line, thereby restarting the diversity receiving system. The algorithm for the judgment in the control unit 9 is shown in FIG.
As shown in FIG. The relationship between each reception level and the diversity reception ON / OFF is as shown in FIG.

FIG. 5 is a block diagram showing a configuration of a mobile radio station for explaining a second embodiment of the present invention. 2, numerals 1 to 8 are the same as those in FIG. 2, and reference numeral 10 denotes a storage detection circuit for detecting that the whip antenna is stored.

In this embodiment, regardless of the comparison result of the reception levels L1 and L2, when the storage detection circuit 10 detects that the whip antenna is stored, the selector 7 stops diversity reception, A method is adopted in which the receiving system is used only with the transmitting and receiving antenna. Of course, in addition to the storage detection, it is further checked whether or not the average value L1 of the reception level L1 for a certain period of time is lower than a certain value Lth1. You need to protect against outages. Thereafter, when the average value of L1 for t seconds becomes larger than a certain prescribed value Lth2, the selector 7 is caused to perform a selection operation by a comparator output, and the diversity receiving system is restarted.

FIG. 6 is a flowchart of a control algorithm according to the second embodiment, and FIG. 7 is a diagram illustrating a reception level, a whip antenna housing detection timing, and diversity reception ON / OF.
The relationship of F timing is shown.

FIG. 8 is a block diagram showing a configuration of a mobile radio station for explaining a third embodiment of the present invention. Numerals 1 to 9 are the same as those in FIG. This embodiment corresponds to the second aspect of the present invention. That is, the invention of claim 2 monitors the reception status of the confirmation signal from the radio base station when the signal is transmitted from the mobile radio station to the radio base station, and determines whether or not to perform diversity reception according to the result. As the signal from the mobile radio station to the radio base station, a location registration signal, a calling signal, and various other signals can be used.

A description will be given below with reference to FIG. 8 and FIG. 9 which is a flowchart showing an example of a control algorithm according to this embodiment. In FIG. 9, S-1 indicates that the mobile radio station is in a standby state (in a system in which all mobile stations receive in common,
(Selection of the control channel has been completed), and in step S-2, the standby diversity reception is turned ON, and the control of the present method is started.

First, it is determined whether or not it is necessary to register the position of the own station on the system side (position registration) (S-3), and if necessary, a position registration request signal is transmitted (S-4). Waiting for reception of a completion signal such as location registration reception (S-5). If reception is not possible within a predetermined time, a recycle operation is performed. If recycle over is performed (S-6), radio waves from the mobile radio station move. Since it is determined that the signal has not reached the radio base station, the diversity reception method is turned off (S-7) to set the reception method only for the transmission / reception shared antenna, and the reception level is determined.
An average value of the reception level over a certain period is obtained (S-1).
2) It is checked whether or not the average L value is lower than a fixed value Lth1 (S-13). If the average L value is lower than Lth1, the reception method using only the common antenna for transmission and reception is continued. Thereafter, an average value of a fixed reception level of only the transmission / reception shared antenna is obtained (S-14), and when the average value L 'becomes larger than a certain prescribed value Lth2 (S-15), the diversity reception system is restarted. Let it.

In the above description, the location registration operation has been described, but also during the call operation (S-8), the transmission request signal is transmitted (S-9), and the reception of the completion signal such as the reception of the transmission request is waited. (S-10) If the signal cannot be received within a predetermined time, the recycle operation is performed, and if the recycle is over (S-11), the diversity reception method is turned off as in the case of (S-6). It is possible to perform the same control as in the case of the location registration operation. Of course, the incoming call operation can be similarly considered.

As described above, after the reception antenna gain is balanced based on the reception status of the response signal from the radio base station to the signal transmission from the mobile radio station,
By determining the standby level and setting the standby state, unnecessary radiation and the number of recycles of transmission and registration signals can be reduced, unnecessary load on the system side can be reduced, and the power supply battery of the mobile station can be reduced. Unnecessary wear can be suppressed. Further, as another embodiment, in addition to the combination of the above embodiments, for example, when diversity reception is stopped, the gain of the transmission / reception shared antenna is greatly reduced to the mobile radio station user by display or sound. A configuration in which the user is notified of the fact and the user pulls out the whip antenna to thereby improve the communication state may be used.

[0020]

As described above, according to the present invention,
For example, a whip antenna is used as a shared antenna for transmission and reception, and a reception-only antenna is built in the housing of the portable device.
In a mobile radio station configured to perform diversity reception using both of these antennas, even when the whip antenna is housed in the housing of the portable device, the transmission from the portable device is sufficient even if the reception level is sufficient. There is an advantage that it is possible to prevent the inconvenience that radio waves do not reach the radio base station from occurring. As a result, it is possible to reduce the deviation from the sense of use that the radio waves from the mobile radio station do not reach the radio base station and cannot be used, despite being within the service area. It is possible to reduce unnecessary load on the mobile station, and it is possible to suppress unnecessary consumption of the power supply battery of the mobile station.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of an antenna configuration of a mobile radio station.

FIG. 2 is a block diagram showing a configuration of a mobile radio station according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating control according to the first embodiment.

FIG. 4 is a diagram illustrating a relationship between a reception level and control of diversity reception.

FIG. 5 is a block diagram illustrating a configuration of a mobile radio station according to a second embodiment of the present invention.

FIG. 6 is a flowchart illustrating control according to the second embodiment.

FIG. 7 is a diagram illustrating a relationship among a reception level, a whip antenna housing detection timing, and diversity reception ON / OFF.

FIG. 8 is a block diagram illustrating a configuration of a mobile station according to a third embodiment of the present invention.

FIG. 9 is a flowchart illustrating control according to the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Common antenna for transmission / reception 2 Antenna for exclusive use of reception 3 Duplexer 4 Transmitter 5, 6 Receiver 7 Selector 8 Comparator 9 Control part 10 Storage detection circuit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-337931 (JP, A) JP-A-56-65533 (JP, A) JP-A-60-52132 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) H04B 7/02-7/12 H04B 7/24-7/26 H04L 1/02-1/06 H04Q 7/00-7/38

Claims (2)

(57) [Claims] In a mobile radio station using a diversity reception system composed of a transmission / reception shared antenna and a reception-only antenna, a reception electric field level at a transmission / reception antenna and a reception electric field level at a reception-only antenna are monitored to be constant. The average value of each level in the time is compared, and the average value of the reception level at the shared antenna is lower than the average value of the reception level of the reception antenna by a predetermined value or more, and If the absolute value of the reception level is less than a certain value, stop diversity reception and switch to the reception method using only the transmission / reception antenna, and then, if the reception level exceeds a certain value, connect to the reception / transmission antenna. A diversity reception method in a mobile radio station, wherein the diversity reception method using a dedicated antenna is restarted. 2. A mobile radio station using a diversity reception system composed of a transmission / reception shared antenna and a reception-only antenna, in which a signal must be transmitted to a radio base station and its confirmation signal must be received. When the number of times that the confirmation signal cannot be received even though the signal has been transmitted to the station exceeds a certain value N, the reception level of the common antenna for transmission and reception is monitored. If the reception level is lower than a certain value, diversity reception is performed. A mobile radio system characterized by stopping and switching to a reception system using only the transmission / reception shared antenna, and then restarting the diversity reception system using the transmission / reception shared antenna and the reception-only antenna when the reception level exceeds a certain value. Diversity reception system at the station.