JPH1094023A - Radio system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely perform communication with a central equipment through a mobile station and a base station by digitally converting a reception input voltage level from the mobile station received in the base station in an A/ D conversion part. SOLUTION: This system is composed of the plural base stations 102-1 and 102-2, the central equipment 103 for remotely operating the base stations and the mobile station 101. In the base stations 102-1 and 102-2, a radio part performs radio wave propagation with the mobile station 102 and a reception input voltage detection part detects a radio wave level from the mobile station 102. Then, the detected radio wave level is A/D converted and turned to digital signals in the A/D conversion part and the respective kinds of signals for monitoring and controlling the base stations and the signals required for the communication with the mobile station 101 are information-transmitted to the central equipment 103 in a digital transmission part. Further, radio is controlled in a control part. The central equipment 103 receives the voltage levels from the base stations in the digital transmission part, compares and judges them by an inter-base-station reception input judgment part and controls the respective base stations in a base station control part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a system for automatically selecting a base station in a radio system such as a train radio system.

[0002]

2. Description of the Related Art FIG. 2 shows a configuration example of a conventional train radio system.
Shown in The train radio system includes a plurality of base stations 2-1 and 2-2.
-2, ground equipment of the central unit 3 for remotely controlling the base station, and the mobile station 1. Base stations 2-1 and 2-2
Controls a radio unit for transmitting and receiving radio waves to and from the mobile station, a reception input voltage detection unit for detecting a received input voltage level, a reception input voltage determination unit for determining whether the reception input voltage level is high or low, and a radio unit And a transmission unit for transmitting various signals to and from the central device 3. On the other hand, the central unit 3 includes a transmission unit that transmits various signals to each of the base station devices 2-1 and 2-2, and a mobile station 1 and a radio link based on the reception input voltage level determination result transmitted from each base station. It comprises a base station reception input voltage determination unit for determining the best base station to connect to, and a control unit for remotely controlling the base stations 2-1 and 2-2.

FIG. 3 shows an example of the reception input voltages of the base stations A and B. The reception input voltage determination unit of the base station makes a determination based on two levels of detection level A and detection level B. That is, if the level is equal to or higher than the detection level A, it is determined that an S / N level sufficient for communication with the mobile station is secured.
/ N is insufficient, but it is determined that the wireless channel is connected, and if the detection level is less than B, it is determined that the wireless channel cannot be connected to the mobile station. Each base station transmits this determination result to the inter-base-station reception input voltage determination unit of the central unit via the transmission unit. The inter-base-station received input voltage judgment unit of the central unit transmits the judgment result to the base station control unit in the central unit so that the base station having the detection level A or higher is connected to the mobile station. The base station control unit in the central unit transmits information to the control unit of the corresponding base station via the transmission unit, and controls the radio unit of the base station. If each base station does not have the detection level A or higher, a base station having the detection level B or higher is selected and the same control as described above is performed. When a plurality of base stations have the same detection level, a priority is assigned to each base station, and the base station with the highest priority is line-connected to the mobile station.

[0004]

In the above-mentioned prior art,
Since the received input voltage level of each base station fluctuates depending on the position of the mobile station, the base station and the base station move to a position where the received input voltage levels of the two base stations are the same and the level fluctuation is large, such as near the midpoint of the base station. When there is a station, there is a drawback that an optimum base station cannot be selected and the radio line is disconnected. An object of the present invention is to solve this drawback and to more reliably perform communication between a mobile station and a central unit via a base station.

[0005]

According to the present invention, in order to achieve the above object, a reception input voltage level from a mobile station received by a base station is converted into a digital signal by an A / D converter, and the reception input voltage of the base station is converted to a digital signal. The level is connected to a reception input determination circuit between base stations of the central unit via a digital transmission unit. The reception input determination unit between base stations of the central unit compares and determines the reception input voltage level from each base station that has been converted into a digital signal, and controls the base station so that the optimum base station is connected to the mobile station by radio line. It is configured to control the radio section by controlling the radio section and connecting to the control section of the base station via the digital transmission section.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 1 is a block diagram showing a configuration of a train radio system according to one embodiment of the present invention. Plurality of base stations 102-
1, 102-2 and a central unit 10 for remotely controlling the base station
3 and the mobile station 101. Base station 102-
Reference numerals 1 and 102-2 denote a radio unit for performing radio wave propagation with the mobile station 101, a reception input voltage detection unit for detecting a radio wave level from the mobile station 101, and A / D conversion of the detected reception input voltage level to generate a digital signal. A / D conversion unit, a digital transmission unit for monitoring and controlling the A / D converted digital signal and various signals for monitoring and controlling the base station, and a digital transmission unit and a radio unit for transmitting information necessary for communication with the mobile station to and from the central unit 103. And a control unit.

[0007] The central unit 103 is connected to each base station 102.
-1 and 102-2, a digital transmission unit for transmitting information, a digital signal which is a reception input voltage level transmitted from each base station, and a base station reception input voltage determination unit for determining an optimum base station. According to the determination result, each base station 10
2-1 and 102-2 having a base station control unit for remote control.

FIG. 3 shows an example of the reception input voltage levels of the base stations A and B. According to the present invention, the reception input voltage levels of the base stations A and B are A / D converted into digital signals, which are directly input to the inter-base station reception input voltage determination section of the central unit via the digital transmission section. Therefore, regardless of the position of the mobile station, the mobile station is connected to the one with the higher received input voltage. At the point A in FIG. 3, since both base stations have the detection level A or higher in the prior art, the base station A
If the priority is given to the wireless station connection with the mobile station, the mobile station is connected to the base station A. However, according to the present invention, the base station B having a high reception input voltage level is connected to the wireless station and connected to the base station A. Information communication can be performed with better quality than at the time.

[0009]

As described above, according to the present invention, for example, in a radio system such as a train radio system in which a mobile station moves in a fixed place and needs to cover a communication area over the whole line, Even if the received input voltage level during the period is low and fluctuates drastically, it is extremely effective because an optimum base station is selected according to the received input voltage level received by the base station and communication with the mobile station is performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing the overall configuration of a conventional wireless system.

FIG. 3 is a diagram showing an example of reception input voltage levels of a base station A and a base station B.

[Explanation of symbols]

 1, 101: mobile station; 2-1, 2-2, 102-1, 102-2: base station; 3, 103: central unit.

Claims (1)

[Claims] 1. A wireless system having a plurality of base stations, a central unit, and a mobile station, wherein the mobile station performs wireless communication with one of the plurality of base stations. A reception input voltage detection section for detecting a reception input voltage level received by the radio section, and an A / D converter for converting the reception input voltage level into a digital signal
/ D conversion unit, and a digital transmission unit that transmits the digital signal and a signal necessary for monitoring and controlling the base station and communicating with the mobile station to the central unit. A base station receiving input voltage determining unit for selecting a base station by comparing the digital signal obtained by A / D conversion of the received input voltage level, and controlling connection between the mobile station and the wireless communication line based on the determination result of the determining unit. A wireless system, characterized by: