JPH02276323A - Communication equipment - Google Patents

Abstract

PURPOSE:To evade the raising of a bit rate and to prevent the activity efficiency of a radio frequency from being lowered by performing line switching by effectively utilizing a space diversity receiver. CONSTITUTION:The switching of a reception channel with the radio frequency f1 and a time slot A to a reception channel with the radio frequency f2 and a time slot F is performed in such a way that a control circuit 19 interrupts reception by a space diversity reception system, and controls a receiver 6 after fixing a selection circuit 11, for example, so as to select the output signal of a receiver 2, and switches sequentially the radio frequency to receive, and informs effect to use the radio frequency and the time slot to an opposite station when a corresponding time slot is available, and switches the selection circuit 11 to the side of the receiver 6, and also, switches the reception channel of the receiver 2, then, restarts the reception by the space diversity reception system.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is directed to TDMA/11'DMA (Time Di
vision Multiple Access7/Pr
Equency Division Multiple
The present invention relates to a communication device using the Access) communication method.

(Conventional technology) In mobile communications, etc., when switching zones.

You may need to switch the line you are using to another line.

Conventionally, 5CPC/FDMA (Single Cha
Nnel Per Carrier/Frequency
y Division Multiple Access
s) As a line switching method for communication equipment based on the communication method, is there an empty frame for every N frames for information transmission? A method was proposed in which lines are switched during this empty frame period ([IEICE Technical Research Report J 88 (293] (1988-11-22) IEICE 9.8l-86). .

(Problem to be Solved by the Invention) However, the line switching method of a communication device based on the above 5CPcA'DMA communication method can be used as is for TDMA/1"DM.
When applied to a communication device based on the A communication method, there is a problem in that the bit rate in the transmission path becomes high because an empty frame is provided for one line switching, and the radio frequency usage efficiency decreases.

The present invention has been made to solve the above-mentioned problems, and by effectively utilizing a base diversity receiver to perform line switching, it is possible to avoid an increase in the transmission rate, and to utilize radio frequencies. An object of the present invention is to provide a communication device that prevents a decrease in efficiency.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides TDMA/il'D
An MA type communication device includes two receivers that perform space diversity reception, a selection circuit that switches and outputs the output signal of the receiver, a monitoring circuit that monitors the quality of the output signal of the receiver, and the Space diversity reception is stopped based on the monitoring result of the monitoring circuit or the designation of the partner station, the receiver whose output signal is not selected by the selection circuit is switched to a new receiving channel, and the quality of the output signal in the switched receiving channel is determined. Is that the standard value? When satisfied, the output signal is selected by the selection circuit and another receiver is switched to the new reception channel to perform space diversity reception? and a control circuit for restarting.

(Function) When it becomes necessary to switch the reception channel when receiving with the S4-S diversity reception method,
Is the control circuit space diversity reception first? - The selection of the receiver output signal by the 1 selection circuit is fixed to either one. Next, the receiving channel of the receiver whose output signal is not selected by the selection circuit is switched to a new receiving channel, and the quality of the output signal of the switched receiver is monitored by the monitoring circuit. When the quality satisfies the reference value, the selection circuit? and select and output the output signal of the switched receiver, switch the receiving channel of the other receiver to the new receiving channel, and set the receiving channels of both receivers to the new receiving channel. 1.Restart normal bus diversity reception.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing a frame structure of a received signal.

In Figure 2 (a), the radio frequency is fl and one frame is A, B.
.

A received signal consisting of three time slots of C? In Fig. 2(b), one frame is shown at the wire frequency f2.

A received signal consisting of three time slots E and F is shown.

First, a case will be described in which reception is performed using a normal bus diversity reception method.

Assume that the radio frequency is fl and time slot A is assigned. TDMA received on antenna 23.24
The received signals of the /rDMA system are input to receivers 2 and 6 via terminals 1.5, respectively. The control circuit 19 sends a control signal to the terminal 20 to the receiver 2 so that the receivers 2 and 6 receive the signal with the radio frequency f and the time slot A.
．． The signal is transmitted through the control terminal 3, and is transmitted to the receiver 6 through the terminal 2 and the control terminal 7. Therefore, the receivers 4 and 6 output signals corresponding to time slot A through the output terminals 4 and 8, respectively. Each of the output signals is sent to terminal 9. l0f (is input to the selection circuit 11 through terminals 14 and 15f, and a portion thereof is input to the quality monitoring circuit 16 through terminals 14 and 15f. The reception level of the reception signal of each receiver 2, 6.

Code error rate etc? The quality of the line is monitored by measuring and the result is sent to the control circuit 19 through terminals 17 and 18'fz.
to notify. Based on the notification, the control circuit 19 sends a control signal to the terminal 2 for selecting the output signal of the line with good quality.
2. Send to selection circuit 1) through 12f. Therefore, from the 1 selection circuit 11.

Of the output signals of the receivers 2 and 6, the one with better quality is output, and is output from the output terminal 13 to the outside. In this way, reception is performed using the normal space diversity reception method.

Next, when receiving 1 normal space divergence.

A case where the quality of the output signals of the receivers 2 and 6 both deteriorate and no longer satisfy the reference value will be described. This state occurs when switching zones in a cellular mobile communication system. When the control circuit 19 learns that the quality of the output signals of the receivers 2 and 6 has deteriorated due to the signal from the quality monitoring circuit 16 and that they no longer satisfy the reference value, the control circuit 19 sends a signal to the selection circuit 1 through the terminals 22 and 12f. Send a control signal, fix 1 selection to one direction, and stop Space Diaper 7 reception. here.

It is assumed that the receiver 2 is fixed to the receiver 2 side, and the output signal of the receiver 2 is output to the output terminal 13. Next, when the control circuit 19 is instructed by a partner station (not shown) to use a reception channel whose radio frequency is f2 and whose time slot is F as shown in FIG. 2(b), for example, , the terminal 21 . , so that the output signal is received by the receiver not selected by the selection circuit 1 , that is, the receiver 6 , on the reception channel with the radio frequency f 2 and the time slot F. A control signal is sent through the control terminal 7. As a result, the receiver 6 outputs an output signal corresponding to the time slot F, and inputs it to the quality monitoring circuit 16 through the terminal 8.15f. On the other hand, the receiver 2 is still receiving on the reception channel with the radio frequency fl and the time slot A, and the signal corresponding to the time slot A is output from the output terminal 13 via the selection circuit 11. The quality monitoring circuit 16 monitors the quality of the output signal from the receiver 6 and informs the overall control circuit 19 accordingly. When the quality satisfies the standard value, the control circuit 19 controls the radio frequency f to the receiver 2.
At terminal 20.2, the time slot is set to receive on the receiving channel of F. A control signal is sent through the control terminal 3, and the output signal of the receiver 6 is sent to the 1 selection circuit 1. A control signal is sent through terminal 22°12 to select. The selection circuit 11 outputs a signal corresponding to time slot F instead of a signal corresponding to time slot A based on the control signal.

Thereafter, reception begins using the Svene diversity reception method described above. That is, the quality of the output signals from the receivers 2 and 6 is monitored by the quality monitoring circuit 16.

Based on the result, the selection circuit 11 is controlled to select the signal with better quality and output it from the output terminal 13. Note that hitless switching can be performed by synchronizing the switching timing of the selection circuit 1 with a clock signal.

Furthermore, in the embodiments described above, the radio frequency is f2 from the reception channel with the radio frequency fl and the time slot A.
To switch to the reception channel with time slot F,
This is done under the initiative of the other station, but the own station may also take the initiative. Namely.

The control circuit 19 stops reception using the Space Diper 7-chi reception method and fixes the selection circuit 1 to select, for example, the output signal of the receiver 2, and then controls the receiver 6 to select the radio signal to be received. The frequency is sequentially switched, and the presence or absence of an empty time slot of good quality is monitored each time.

If a suitable time slot is found, its radio frequency and time slot? Notify the partner station that it will be used, switch the selection circuit 1 to the receiver 6 side, and switch the reception channel of the receiver 2 to receive the radio frequency and time slot, using the Space Diaper 7ch reception method. Resume reception.

(Effects of the Invention) As described above in detail, according to the present invention, TDMA
/1;”With DMA communication devices, it is possible to switch reception channels using the Space Diaper 7ch receiver without disconnecting the current communication line, so it is possible to switch reception channels from one base station to another, such as a car phone. It is very effective when applied to a system in which communication is performed while sequentially switching base stations υ, since switching can be performed without disconnection of the line.

Further, since there is no need to provide a time slot for switching reception channels, it is possible to avoid an increase in the bit rate, and it is possible to construct a communication system with high efficiency in the use of radio frequencies.

Furthermore, since the Space Diper 7-chi receiver, selection circuit, etc. are effectively utilized, an economical device can be realized.

[Brief explanation of drawings]

Is Figure 1 an embodiment of the present invention? The block diagram shown in FIG. 2 is a frame configuration diagram of a received signal. 7.5, 9, 10, 12, 14, 15, 17.18.2
0-22...terminal, 2,6...receiver, 3,7...
・Control terminal. 4.8.13... Output terminal, 11... Selection circuit, 1
6... Quality monitoring circuit, 19... Control circuit, 23.2
4...Antenna.

Claims (1)

[Claims] A TDMA/FDMA type communication device, comprising at least two receivers that perform space diversity reception, a selection circuit that switches and outputs an output signal of the receiver, and an output signal of the receiver. a monitoring circuit that monitors the quality of the signal; and a monitor circuit that discontinues space diversity reception based on the monitoring result of the monitoring circuit or the designation of the partner station, and switches the receiver whose output signal is not selected by the selection circuit to a new reception channel. , when the quality of the output signal in the switched reception channel satisfies a reference value, the selection circuit selects the output signal, switches another receiver to the new reception channel, and resumes space diversity reception. A communication device characterized by comprising a control circuit that performs the following steps.