JPH04144428A - Mobile radio communication system - Google Patents

Abstract

PURPOSE:To secure a sufficiently long distance between the antennas of radio base stations, to obtain an effective communication state and to use only one receiving system by executing diversity reception between plural different radio stations in the same radio zone. CONSTITUTION:Radio base stations 13a, 13b are allocated to the same radio zone and a lone ccontroller 11 is provided with a comparator 26 connected to a switching circuit 22 as a comparing means for mutually comparing signals received by the stations in the same radio zone based upon the measured result of a reception level detection circuit, a selective circuit 27 to be a selective means for selecting a radio channel with high communication state at every incoming signal based upon the compared result of the comparator 26 and sending an outgoing signal to its corresponding radio telephone set and a deversity control means including a part of a controller 24. Consequenty, the distance between the antennas of the stations 13a, 13b can be sufficiently secured, an effective communication state can be obtained and reception can be attained only by one receiving system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is utilized in a mobile radio communication system of a cordless telephone system. In particular, it relates to a diversity mobile radio communication system.

〔overview〕

In a mobile radio communication system, the present invention performs diversity reception between a plurality of different radio base stations in the same radio zone, thereby making it possible to maintain a sufficient distance between the antennas of the radio base stations and thereby achieving good communication. The system is designed so that the state can be obtained and only one receiving system is required.

[Conventional technology]

FIG. 6 is a block diagram of a conventional mobile radio communication system. FIG. 7 is a block diagram of a diversity receiving circuit for a conventional mobile radio communication system. FIG. 8 is a diagram showing a calling sequence in a conventional mobile radio communication system.

Conventionally, a mobile radio communication system has a configuration as shown in FIG. That is, the wireless telephone 65 exists within the wireless zone of the wireless base station 62, and the wireless base station 62
3.64 and performs diversity reception. One method of diversity reception is to use two or more receiving antennas that are sufficiently spaced apart, provide paths with independent fading, and select the detected output signal with a higher reception level.

FIG. 7 shows an example of a diversity receiving circuit using a selective combination method in a radio base station device, in which 71a171b is an antenna, 72a, 721) is a frequency conversion circuit, and 73a is a diversity receiving circuit using a selective combination method.
, 73b is a detection circuit, 74a and 74b are reception level detection circuits, 75 is a reception level comparison circuit, and 76 is a signal selection circuit. In the selective synthesis method, radio waves transmitted from the radio telephone 65 are combined with two antennas 71a, for example.
, 71b and the frequency conversion circuit 72a, 7
2b to intermediate frequency signals, and the detection circuit 73
The signal is taken out at a and 73b. Frequency conversion circuit 72a
, 72b are detected by the reception level detection circuit 74a.
, 74b, and the comparison circuit 75 detects the level. Based on the result, the selection circuit 76 selects the signal with the higher reception level. Next, from the wireless base station 62 to the wireless telephone 65
When transmitting a signal, the radio waves are emitted from the antenna with the highest reception level.

In this way, two systems of receiving devices are used up to the detection circuit, and the detection output signal with the higher reception level is selected, thereby maintaining a better communication state. It has features such as simple operation, high reliability, and high diversity gain.

In FIG. 8, when the wireless telephone 65 makes a call, the wireless telephone 65 transmits a calling signal 81 to the wireless base station 62.
The calling signal 81 received is sent to the line control device 61. The line control device 61 returns a call response signal 82 to the wireless base station 62. Thereafter, the radio telephone 65 sends out a dial signal 83, and similarly, the dial signal 83 received by the radio base station 62 is sent to the line control device 61. The line control device 61 returns a dial acceptance signal 84 to the wireless base station 62.

Next, the radio base station 62 transmits a speech channel designation signal 85 to the radio telephone 65, and the radio telephone 65 switches to the designated speech channel and sends a speech channel switching completion signal 86 to the line via the radio base station 62. The information is transmitted to the control device 61, and a communication path is thereby set up.

In the above sequence, the radio waves transmitted from the radio telephone 65 to the radio base station 62 are received by the antennas 63 and 64, and the diversity receiving circuit in the radio base station 62 selects the signal with a high reception level.

[Problem to be solved by the invention]

However, in such conventional mobile radio communication systems, the radio base station equipment is mounted on walls or ceilings, so there is a tendency for the radio base station equipment to be smaller and lighter in terms of appearance and ease of installation. For example, at 2.6 GHz, the distance between the antennas must be approximately 5 Q cm to 1 m, and two (or more) antennas must be installed in the wireless base station equipment. ) Even if an antenna was installed, there was a problem in that it was difficult to obtain the full effect.

Furthermore, when performing spatial diversity reception, two systems of receiving devices are required in the radio base station apparatus.

When using many wireless terminals within the same wireless zone,
Although multiple wireless base stations may be installed to connect multiple terminals at the same time, there are only a few wireless base stations that are in constant use, and the majority are not in use. This has led to problems such as waste and expensive equipment.

The present invention solves the above-mentioned problems, and enables a sufficient distance between antennas for spatial diversity reception, a good communication condition, and a single system of receiving equipment for radio base station equipment. The purpose is to provide a wireless communication method.

[Means to solve the problem]

The present invention comprises a plurality of radio base stations each including a plurality of radio telephones and a radio transmitting/receiving means for communicating with each other via a radio line, and a line control device for controlling the plurality of radio base stations. In a mobile radio communication system that includes measuring means for measuring the quality of uplink signals from each radio telephone and providing the measurement results to the line control device, the radio transmitting and receiving means of the base station transmits the two or more radio base stations at the same time. allocated to a wireless zone, and the line control device includes a comparing means for comparing uplink signals received by the plurality of wireless base stations for each same wireless zone based on the measurement results of the respective measuring means, and a comparison means based on the comparison results of the comparing means. The present invention is characterized in that it includes a diversity control means including a selection means for selecting a radio line with a good communication condition for each uplink signal and transmitting a downlink signal to the corresponding radio telephone.

Further, in the present invention, the line control device may include means for allocating an empty radio base station among the two or more radio base stations to perform diversity transmission and reception.

Further, in the present invention, the radio base station and the radio transmitting/receiving means of each radio telephone may be configured to communicate using the same uplink and downlink frequencies.

[Effect]

Diversity control is performed by assigning two or more wireless base stations to the same wireless zone. That is, the wireless base station measures the quality of uplink signals from each wireless telephone using a measuring means and provides the measurement results to the line control device. The diversity control means of the line control device uses a comparison means to compare uplink signals received by a plurality of radio base stations for each same radio zone based on the measurement results of the respective measurement means. Based on the comparison result of the comparison means, the selection means selects a radio line with a good communication condition for each uplink signal and sends it to the corresponding radio telephone.

Further, the line control device may allocate an empty radio base station among the two or more radio base stations to perform diversity transmission and reception.

Furthermore, the radio transmitting and receiving means of each radio base station and each radio telephone may communicate using the same uplink and downlink frequencies.

As a result of the above, it is possible to maintain a sufficient distance between the antennas of wireless base stations, obtain good communication conditions, and also have a receiving system with a single reception system.
It can be done systematically.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram of a mobile radio communication system according to an embodiment of the present invention. FIG. 2 is a block diagram of a line control device for a mobile radio communication system according to the present invention. FIG. 3 is a block diagram of a radio base station of the mobile radio communication system of the present invention. Fourth
The figure is a block configuration diagram of a wireless telephone using a mobile wireless communication system according to the present invention. 1 to 4, the mobile radio communication system includes a plurality of radio telephones 15 and respective radio lines 12.
The line control device 11 includes a plurality of wireless base stations 13 including wireless transmitting/receiving means for communicating with each other via a telephone network, and a line control device 11 that controls the plurality of wireless base stations 13. interface circuit 21
, a switch circuit 22 that connects the line between the general telephone network and the cordless telephone system, a switch circuit 22, an interface circuit 23 with the wireless base station 13, and a control device 24.
and a memory 25, and the wireless transmitting/receiving means of each wireless base station 13 includes an antenna 14, a wireless transmitter/receiver 32, an interface 33 with the line control device 11, and a control device 35.
Each radio telephone 15 includes an antenna 41, a radio transceiver 42, a control device 43, a display device 44, a memory 45, and an audio circuit 46, and further includes an antenna 41, a radio transceiver 42, a control device 43, a display device 44, a memory 45, and an audio circuit 46. 13a and 13b are connected to the radio transceiver 32 and include a reception level detection circuit 34 and a part of the control device 35 as measuring means for measuring the quality of the upstream signal from the radio telephone 15.

Here, the feature of the present invention is that the wireless base station 13a
, 13b are assigned to the same radio zone, and the line control device 11 uses a switch circuit 22 as a comparison means to compare the signals received by the radio base stations 13a and 13b for each same radio zone based on the measurement result of the reception level detection circuit 34. A selection circuit 27 and a control circuit are used as selection means for selecting a radio line with good communication condition for each uplink signal based on the comparison result of the comparison circuit 26 and sending the downlink signal to the corresponding radio telephone. A diversity control means comprising part of the device 24 is provided.

Also, wireless base stations 13a, 13b and wireless telephone 1
The wireless transceivers 32 and 42 of No. 5 are configured to communicate by time division multiplexing using the same uplink and downlink frequencies.

[References, Proceedings of the 1990 Spring National Conference of the Institute of Electronics, Information and Communication Engineers, Microcell Digital Mobile Communications Using Multicarrier TDMA/TDD, B-335, for Hori.

Others: Journal of the Institute of Electronics, Information and Communication Engineers, Technical Trends in Cordless Telephone Systems,
P857-860. Vol, 73.1990-8
．． Hesaka, et al.] The operation of a mobile radio communication system having such a configuration will be explained.

FIG. 5 is a diagram showing a calling sequence of the mobile radio communication system of the present invention.

FIG. 5 shows a calling sequence from when the wireless telephone 15 sends a calling signal to the cordless telephone system until a call response signal is returned, and two wireless base stations 13a and 1 are called.
3b is a sequence of a diversity reception method when using 3b.

In FIGS. 1 to 5, when the wireless telephone 15 makes a call, the wireless base station 13a serving the same wireless zone
, 13b detect the reception level of the calling signal 51 sent from the radio telephone 15, and then send reception level notifications 53a, 53b to the line control device 11. The line control device 11 compares the reception level notifications 53a and 53b from the wireless base stations 13a and 13b in the comparison circuit 26, and if the reception level notification 53a received at the wireless base station 13a is higher, the selection circuit 27 selects the radio base station 13a with a high reception level, and uses the control device 24 to receive the calling signal 51 from the radio base station 13a. Next, the selection result notification 57 is notified to each radio base station 13a13b, and the line control device 11 transmits a call response signal 58 to the radio telephone 15 via the radio base station 13a having a high reception level.

In this way, a plurality of radio base stations detect the reception levels of transmission signals from radio telephones, and the line control device compares the reception levels and selects the signal with the higher level. When transmitting to a wireless telephone, the signal is transmitted from the wireless base station receiving the signal at this high level.

Also, between a wireless telephone and a cordless telephone system,
Sending dialing signals and confirming delivery, specifying communication channels,
The second method can also be used when transmitting and receiving switching completion signals, call signals, and the like.

Furthermore, it is also possible to similarly perform spatial diversity using three or more wireless base stations to obtain a diversity effect.

When a plurality of radio base stations serving the same radio zone are frequently used for telephone calls, spatial diversity in call connections and telephone calls as described above becomes possible.

In this case, for example, there is a method of discontinuing diversity in calls, providing an empty radio base station, and performing diversity by giving priority to control channels. Furthermore, for example, if there is only one radio base station that controls call connections in the same radio zone, there is a method of using one of the other radio base stations for diversity and not using it for calls.

〔Effect of the invention〕

As explained above, the present invention has the excellent effect that a sufficient distance between the antennas of radio base stations can be maintained, good communication conditions can be obtained, and the number of receiving systems can be reduced to one.

Especially when a large number of wireless base stations are installed in order to simultaneously connect a large number of wireless terminals within the same wireless zone, there is a great advantage of economicalization.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a mobile radio communication system according to an embodiment of the present invention. FIG. 2 is a block diagram of a line control device for a mobile radio communication system according to the present invention. FIG. 3 is a block configuration diagram of a radio base station of the mobile radio communication system of the present invention. FIG. 4 is a block diagram of a wireless telephone using the mobile wireless communication system of the present invention. FIG. 5 is a diagram showing a calling sequence of the mobile radio communication system of the present invention. FIG. 6 is a block diagram of a conventional mobile radio communication system. FIG. 7 is a block diagram of a diversity receiving circuit in a conventional mobile radio communication system. FIG. 8 is a diagram showing a calling sequence of a conventional mobile radio communication system. 11.61--Line control device, 12a, 12b,
60--wire line, 13a, 13b-wireless base station, 14.14a, 14b. 41.63.64.71a, 71b-...Antenna, 15.65...Radio telephone, 2L 23.33...
・Interface, 22...Switch circuit, 24.3
5.43...Control device, 25.36.45...Memory, 26.75...Comparison circuit, 27.76...Selection circuit, 32.42-...Wireless transceiver, 34.74a
, 74b - Reception bell detection circuit, 44 - Display device, 46 - Audio circuit, 51.81 - Calling signal, 52a, 52b - Reception level detection, 53a
, 53b...Reception level notification, 54...Reception level comparison, 55...Select high reception level, 56...Selection of transmitting radio base station, 57...Selection result notification, 58...
・Call response signal, 72a, ? 2b... Frequency conversion circuit, 73a, 73b... Detection circuit, 82... Call response signal, 83... Dial signal, 84... Dial acceptance signal, 85... Call channel designation signal, 86・
...Call channel switching completion signal. Patent Applicant Nippon Telegraph and Telephone Corporation Agent Patent Attorney Nao Takashi IdeConventional Example Dynogu-Sichi Umeji Ryozu Conventional Example Party 4 Sea Gyance Sword 8 Illustration

Claims (1)

[Claims] 1. A plurality of radio base stations each including a plurality of radio telephones and a radio transmitting/receiving means for communicating with each other via a radio line;
a line control device that controls the plurality of radio base stations, and the radio transmitting/receiving means of each radio base station measures the quality of the uplink signal from each radio telephone and provides the measurement result to the line control device. In a mobile radio communication system including the above two or more radio base stations, the above two or more radio base stations are assigned to the same radio zone, and the above line control device assigns the above two or more radio base stations to the same radio zone based on the measurement results of each of the above measurement means. diversity control comprising a comparing means for comparing uplink signals received by the comparing means, and a selection means for selecting a radio line with a good communication condition for each uplink signal and transmitting a downlink signal to the corresponding radio telephone based on the comparison result of the comparison means. A mobile radio communication system characterized by comprising means. 2. The mobile radio communication system according to claim 1, wherein said line control device includes means for allocating a vacant radio base station among said two or more radio base stations to perform diversity transmission and reception. 3. The mobile radio communication system according to claim 1, wherein the radio transmitting/receiving means of each of the radio base stations and each of the radio telephones is configured to communicate using the same uplink and downlink frequencies.