JP2793556B2 - PHS connection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection device for a PHS, and more particularly to a control channel for controlling connection with a portable terminal (PS) of a PHS (Personal Handy Phone System: simplified portable telephone system). The present invention relates to a connection device (base station: CS) that manages a wireless channel and performs wireless signal transmission and reception.

[0002]

2. Description of the Related Art In a self-operated (including home-use) system in a PHS, there is no regulation on the transmission timing of a control channel on a radio interface to a portable terminal of a connection device of each system installed at an arbitrary place.
When there are different connection devices in the vicinity, a collision (radio interference) of control signals may occur. In this case, the portable terminal in the standby state, which is synchronized with the control signal of the connection device, cannot synchronize the control channel, and cannot control the transmission and the reception.

[0003]

In a conventional PHS private system, there is no need to install a connection device in consideration of overlapping wireless zones with other systems, and a plurality of private systems are randomly installed in actual use. The Rukoto. In this case, since the control channel frequency is commonly used, the above-mentioned control channel signal collision becomes a problem. In the conventional connection device, it was easy to detect the interference of the uplink (from the mobile terminal to the connection device) signal at the reception timing of the own device,
A method for avoiding the control signal interference between the connection devices of the different systems of the downlink (from the connection device to the mobile terminal) control signal at the transmission timing has not been studied.

An object of the present invention is to provide a PHS connecting device capable of avoiding interference with other surrounding connecting devices by controlling a transmission timing of a control signal based on a measurement result of a received electric field for a downlink signal. To provide.

[0005]

A PHS connection device according to the present invention is a connection device for managing a radio channel including a control channel for connection control with a PHS portable terminal and transmitting and receiving signals by radio. In the transmission timing of the control channel of the own device, when it is determined that there is no need to transmit the transmission data, the transmission is suspended, and the reception electric field value for interference detection is measured at the transmission timing of the control channel. When interference on the control channel with the connection device is detected, the transmission timing of the control channel is changed to avoid the interference.

[0006] In the above configuration, wireless communication means for transmitting and receiving signals to and from a portable terminal through a wireless channel; and reception level measuring means for measuring a reception level of a wireless channel via the wireless communication means; Timing generation means for designating the transmission / reception timing of the wireless channel with respect to the communication means; storage means for storing interference determination conditions for the control channel; It is determined whether or not transmission is necessary, and when it is determined that transmission is not necessary, the wireless communication means is temporarily stopped from transmitting, and the measurement result of the reception electric field value of the control channel by the reception level measurement means at this timing is stored. The interference with other connected devices based on the result of the comparison. Then it can be configured to have a control means for changing the transmission timing of a control channel to said timing generating means.

[0007]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. In FIG. 1, a PHS connection device (CS) of the present embodiment manages a wireless channel with a portable terminal (PS) (not shown) via an antenna 11, performs transmission / reception of a wireless signal, modulation / demodulation, and a wireless channel. 1 including a reception level measuring circuit 12 for measuring the reception level of
A timing generation circuit 2 for generating timing information for designating transmission / reception timing of a wireless channel of the wireless device;
It controls the operation of the entire connection device and performs a reception level measurement circuit 12.
And a non-volatile memory 4 for storing various data necessary for the control of the CPU 3 based on the measurement result. And operates as a base station for the wireless terminal.

FIG. 2 is a diagram showing an example of the structure of a control channel (common control channel) among radio channels. In FIG. 2, a BCCH (broadcast channel) is a connection device (CS).
Is a downlink one-way channel for notifying the mobile terminal (PS) of information on the radio channel configuration, congestion regulation, and the like. PCH (paging channel) is a downlink channel for the CS to perform an incoming call to the PS. Direction channel, SCCH
(Individual cell channel) is a bidirectional channel for establishing a link channel between CS and PS. SCCH
Splits a 5ms 1TDMA frame into 8 slots,
The first four slots are used for downlink (CS-side transmission slots), and the second half are used for uplink (CS-side reception slots). Normally, the SCCH signal is used to specify a communication channel during a connection operation, and is a signal that does not need to be transmitted to the mobile terminal when there is no connection request or the like. Performing the measurement of the reception electric field of the signal of another station (other connection device) without transmitting the signal of the own station at this signal transmission timing when there is no transmission signal does not hinder the portable terminal. The reception electric field measurement is performed by the reception level measurement circuit 12 using the first transmission slot.

Next, the operation will be described. Here, two different
It is assumed that the connection device A and the connection device B of each of the PHS systems share the wireless zone (see FIG. 3). In such a case, as shown in FIG.
And the wireless channel control signals of the two may collide with each other. At this time, the mobile terminal located in the area where the wireless zone of the connection device A and the wireless zone of the connection device B intersect,
The control signals are not synchronized. In a conventional connection device,
In such a case, signal collision with another station cannot be detected. In order to avoid this, in the present invention,
By measuring the received electric field using the transmission timing of the SCCH signal among the downlink signals in the connected device, it is always monitored whether there is a connected device transmitting at a timing that causes signal collision in the vicinity.

The operation of the present invention will be described in more detail with reference to the flowchart of FIG. 5 together with FIGS. When recognizing that the SCCH transmission timing has come from the timing information of the timing generation circuit 2, the CPU 3 of each connection device determines whether SCCH transmission is necessary (step S1 in FIG. 5), allocates an LCH (link channel), Or, when there is no need to transmit such as LCH assignment rejection,
The wireless device 1 is controlled at the transmission timing, and the reception level measurement circuit 12 measures the reception electric field in the first transmission slot (or before and after the first transmission slot), finds the maximum value, and sets the maximum value (step S2). The CPU 3 also sets a time value x (for example, about 10 seconds to 1 minute) and a level threshold z (for example, 30 to 40 μV, or a connection device (CS)) preset in the nonvolatile memory 4 as interference determination conditions. Reads the standby hold level instructed by the PS, and obtains the average value of the reception level values of all the measurements obtained within x time (total reception level value / measurement count) and sets the average value as the average reception level value. Then, it is determined whether or not the average reception level value is equal to or greater than the threshold value z (step S3). If the average reception level value is equal to or greater than the threshold value z, the timing generation circuit 2 is controlled to set the transmission timing of the control signal to a position where no collision occurs. It is changed (step S4). If the average reception level value is not equal to or greater than the threshold value z, the control signal transmission timing is not changed. The set values of the time value x and the threshold value z can be arbitrarily changed by the system. In addition, in the determination processing in step S1, if SCCH transmission is necessary, SCCH transmission is performed, and reception electric field measurement is not performed (step S5). The processes of steps S1 to S5 are constantly and repeatedly executed.

As described above, each connection device detects a signal collision (interference) with another connection device at the downlink (transmission from the connection device to the portable terminal) timing on the control channel to the reception electric field at its own transmission timing. Detected by performing measurement,
By re-determining the transmission timing of the control channel, signal collision of the control channel can be avoided.

[0013]

As described above, the PHS connection device of the present invention monitors the collision of control signals with other connection devices,
At the time of collision detection, by resetting the transmission timing of the control signal to a timing that avoids the collision, it is possible to improve the connectivity with the mobile terminal that is waiting in synchronization with the control signal. In addition, since the mobile terminal does not lose synchronization due to signal collision of the connection device, the battery life of the mobile terminal can be extended.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating a structure example of a control channel and a reception electric field measurement timing among wireless channels.

FIG. 3 is a diagram illustrating a configuration example of a wireless zone of two connection devices.

FIG. 4 is a diagram showing a control signal collision state between the connection devices shown in FIG. 3;

FIG. 5 is a flowchart illustrating a control signal interference avoiding operation according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Radio 2 Timing generation circuit 3 CPU 4 Non-volatile memory 12 Reception level measurement circuit

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI H04Q 7/30

Claims (2)

(57) [Claims] 1. A connection device which manages a radio channel including a control channel for connection control between a PHS and a portable terminal and transmits / receives a signal by radio. When it is determined that there is no need to transmit the transmission, the transmission is temporarily stopped, the reception electric field value for interference detection is measured at the transmission timing of this control channel, and when interference on the control channel with another connected device is detected. A PHS connection device, which changes the transmission timing of the control channel to avoid interference. 2. A radio communication unit for transmitting and receiving signals to and from a portable terminal through a radio channel, a reception level measurement unit for measuring a reception level of a radio channel via the radio communication unit, Timing generation means for designating transmission / reception timing of a wireless channel; storage means for storing interference determination conditions for a control channel; transmission data transmission when transmission timing of the control channel of the own apparatus is recognized with reference to the timing generation means Is determined, the transmission is temporarily stopped by the wireless communication unit when it is determined that it is not necessary, and the measurement result of the reception electric field value of the control channel by the reception level measurement unit at this timing is determined by the interference of the storage unit. It is collated with the judgment condition, and when interference with another connected device is detected based on the collation result, the time PHS connection device according to claim 1, wherein the relative grayed generating means and a control means for changing the transmission timing of the control channel.