JPS63250933A - Switch matrix with fault detecting function - Google Patents

Abstract

PURPOSE:To perform a sure diagnosis without causing a trouble on an application, and to make it possible to diagnose all switch elements by setting a prescribed period in a TDMA frame as a time slot for the diagnosis, and diagnosing the fault of the respective switch element within the said period. CONSTITUTION:A diagnosing RF signal generation circuit 33 outputs a diagnosing RF signal for the prescribed period, prescribed time after the TDMA frame pulse 1. At that time, a diagnosing control signal is impressed to the switch element, which is the object to be diagnosed, from a switch control circuit 34. In a case that the element operates normally, an RF monitor signal can be obtained from output association circuits 13-16, and RF detection circuits 35-38 detect them, and an RF detection signal is obtained. In the case that the element does not operate normally, the RF monitor signal is due either not to be outputted or to be outputted continuously, and the fault of the element is detected. Besides, the circuit 33 outputs the diagnosing RF signal during the period while the TDMA signal is not inputted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides an RF signal for switching TDMA signals on a satellite.
The present invention relates to a /IF switch matrix, and particularly to a switch matrix with a fault detection function that has a function of detecting a fault in a switch element placed at the intersection of an input line and an output line.

(Prior Art) Conventionally known diagnostic methods for this type of switch matrix include
RF/
How to diagnose the connection status of the IF signal, create a pilot signal with a frequency outside the RF/IF signal band, input it from the input line, and monitor and diagnose whether the pilot signal can be correctly output to the output line. There are ways to do this.

(Problems to be Solved by the Invention) However, the former method has the disadvantage that it is not possible to perform reliable diagnosis for some failure modes of switching elements, and the latter method has the drawback that However, there were drawbacks such as a pilot signal being always output to the output line and only switches that were currently in use being able to be monitored.

(Means for Solving the Problems) Means provided by the present invention to solve the above-mentioned problems includes a plurality of input lines for inputting TDMA signals, and a plurality of input lines for inputting TDMA signals.
A switch matrix comprising a plurality of output lines that output MA signals, and a switch element that connects or cuts off the connection between the input line and the output line at the intersection of the input line and the output line, a diagnostic RF signal generation circuit that generates a diagnostic RF multiplied signal; an input coupling circuit that couples the output of the diagnostic RF signal generation circuit to the input line; and an output coupling circuit that extracts an RF monitor signal from the output line; The RF
R that detects the envelope line of the monitor signal and outputs the RF detection signal
an F detection circuit, and a switch control circuit that controls the connection and cutoff of the switch element, and the diagnostic RF
The signal generation circuit always outputs the diagnostic RF multiplied signal only during a certain period after a certain period of time has elapsed from the TDMA frame pulse, and the switch control circuit gives the connection or cutoff signal to the switch element only during the certain period. T above
The switching element is characterized in that the switching element is connected or cut off regardless of the DMA signal.

(Embodiment) FIG. 1 is a circuit diagram showing an embodiment of the present invention. Input lines 1 to 4 are lines for inputting TDMA signals, output lines 5 to 8 are lines for outputting TDMA signals, and input coupling circuits 9 to 12 are lines for inputting RF signals from diagnostic RF signal generation circuit 33 to input line 1.
4, the output coupling circuits 13 to 16 are coupling circuits that take out the diagnostic RF signals (RF monitor signals) switched by the switch elements 17 to 32, and the RF detection circuits 35 to 38 perform diagnosis from the RF monitor signals. The switch control circuit 34, which is a circuit that outputs an RF detection signal corresponding to the RF multiplied signal envelope line, is a circuit that outputs a control signal for controlling connection and disconnection of the switch elements 17 to 32.

FIG. 2 is a diagram showing waveforms of various signals in the embodiment of FIG. 1. TDMA frame pulse (1) is input rDM
This signal indicates the start of a frame of the A signal. After a certain period of time from this frame pulse (1), diagnostic R is used for a certain period of time.
F-fold signal 2) is output.

At this time, a diagnostic control signal (3) is applied from the switch control circuit 34 to the switch element to be diagnosed. When the switch element is normally connected or disconnected, an RF monitor signal (4) is obtained from the output coupling circuits 13 to 16, and the RF detection circuits 35 to 38 detect this RF monitor signal and output the RF signal. Obtain detection signal (5). However, if the switch element is not operating normally, for example if it continues to be cut off, the RF monitor signal will not be output, and if it continues to be connected, the RF monitor signal will not be output during this period. As a result, a fault in the switching element is detected. Note that the diagnostic RFi signal generation circuit 33 outputs a diagnostic RF signal during a period when the TDMA signal cannot be fully input. Further, the switch control circuit 34 changes the switch elements to which the diagnostic control signal is applied for each TDMA frame, and diagnoses the switch elements for one column in each frame.

(Effects of the Invention) As described above, the present invention sets a certain period in a TDMA frame as a diagnostic time slot, and diagnoses a fault in each switch element within that period. Therefore, the present invention has the following effects.

(1) Since the RF/IF signal is monitored, faults in the switching elements can be reliably monitored.

(2) Since the RF double signal for diagnosis is output from the output line during a time slot that is not used in TDMA, there is no problem in operation.

(3) Since the diagnostic RF double signal is applied to the switching element in the diagnostic time slot, the level can be increased to a level sufficient for the diagnostic RF double signal test.

(4) Since diagnosis can be performed regardless of the switching pattern of the TDMA system, diagnosis of all switching elements can be performed without restriction.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention f=J, and FIG. 2 is a diagram showing waveforms of various signals in the embodiment. 1-4...Input line, 5-8...Output line, 9-12.
...Input coupling circuit, 13-16...Output coupling circuit, 1
7-32...Switch element, 33...Diagnostic RF signal generation circuit, 34...Switch control circuit, 35-38
...RF detection circuit.

Claims (1)

[Claims] a plurality of input lines for inputting TDMA signals;
In a switch matrix having a plurality of output lines that output A signals, and a switch element that connects or disconnects these input lines and output lines at the intersection of the input lines and output lines, Diagnostic R that generates RF signals
an F signal generation circuit, an input coupling circuit that couples the output of the diagnostic RF signal generation circuit to the input line, an output coupling circuit that extracts an RF monitor signal from the output line, and detects an envelope of the RF monitor signal. RF that outputs the RF detection signal
The diagnostic RF signal generation circuit includes a detection circuit and a switch control circuit that controls the connection and disconnection of the switch element, and the diagnostic RF signal generation circuit generates the diagnostic RF signal only for a certain period of time after a TDMA frame pulse. and the switch control circuit applies the connection or cutoff signal to the switch element only for the certain period of time to control the TD.
A switch matrix with a failure detection function, characterized in that the switch element is connected or cut off regardless of an MA signal.