JPS5848824Y2 - data receiving device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a data receiving device that receives transmission data, and particularly to a data receiving device that performs long-term gain adjustment using the transmitted data itself and receives it as transmission data at a predetermined level. - related to a data receiving device.

Conventionally, when receiving transmitted data while adjusting the gain,
A circuit as shown in FIG. 1 is used at the input stage of the data receiver.

That is, this circuit includes an integrating circuit 1 that integrates a fixed-format pre-angle code in front of a transmission data frame, and a gain that is adjusted by the integral output of this integrating circuit 1, and converts the input transmission data frame into a transmission frame of a predetermined level. - a variable gain amplifier 2 outputting as a data frame.

The data receiving device as described above receives the transmitted data frame from station m or station n shown in FIG. 2A, but in this case, the transmitting device side The data with the pre-angle code added is sent to the receiving device.

Therefore, in the receiving apparatus shown in FIG. 1, the pre-angle code of several bits in a fixed format before the transmission data frame A is received by the integrating circuit 1 to generate a gain adjustment signal as shown in FIG. 2B in advance. The gain of the variable gain amplifier 2 is adjusted.

As a result, even if transmission data frames I of different levels arrive from stations m, n, etc., it is possible to output the transmission data frames I of a predetermined level from the variable gain amplifier 2.

In the figure, Gmax indicates that the maximum gain adjustment signal is output when there is no data due to the inverting operation of the internal inverter of the integrating circuit 1.

However, in the apparatus shown in FIG. 1, it is necessary for the transmitting side to add a pre-angle code, which should be unnecessary, to the transmitted data frame, and on the other hand, it is necessary for the receiving side to remove the pre-angle code.

Therefore, from the perspective of the data transmission device as a whole, a circuit for adding and removing the pre-angle code is required, resulting in a complicated circuit configuration.
Standard formats such as 5DLC must be broken.

In recent years, there has been a movement toward international standardization of data transmission means, and dedicated LSIs have also been introduced, but the above-mentioned data transmission means have a special drawback.

The present invention was developed in order to eliminate the above-mentioned drawbacks, and it uses the original transmission data itself to create a gain adjustment signal, thereby eliminating the pre-angle code and standardizing the data transmission means. It is an object of the present invention to provide a data receiving device that can simplify the entire data transmission device and stably perform gain adjustment over a long period of time.

An embodiment of the present invention will be described below with reference to FIG.

In the figure, 10 is an input terminal of the receiving device, and this terminal 1
0 contains the transmission data frame.

For example, in the case of an optical communication system, this transmission data frame contains a signal converted into an electrical signal.

Reference numeral 11 denotes a delay circuit that delays a received transmission data frame for a predetermined period of time, and uses, for example, a delay line.

12 is an OR circuit which outputs the transmission data frame received at the input terminal 10 and the transmission data frame delayed by the delay circuit 11;

13 is an integrating circuit, and 14 is a variable gain amplifier.

A variable threshold comparator may be used instead of the variable gain amplifier 14.

Next, the operation of the data receiving apparatus as described above will be explained.

First, it is assumed that transmission data frames as shown in FIG. 4A are transmitted from the transmitting devices of stations m and n.

When this transmission data frame is input to the delay circuit 11 via the input terminal 10, it is delayed for a certain period of time to become a transmission data frame as shown in FIG. 4B, which is input to the OR circuit 12 and the variable gain amplifier 14. Ru.

Since this OR circuit 12 has already received a direct transmission data frame from the input terminal 10, this data frame and the transmission data delayed and output from the delay circuit 11 are combined.
By passing the data frame, a combined transmission data frame as shown in FIG.

By the way, since the integration circuit 13 receives a directly transmitted data frame from the input terminal 10 via the OR circuit 12, it integrates this to create a gain adjustment signal (see the fourth diagram) and adjusts the gain of the variable gain amplifier 14. It will have to be adjusted.

Furthermore, since the transmitted data frame delayed by the delay circuit 11 passes through the OR circuit 12 and enters the integration circuit 13, this integration circuit 13 continues to create a gain adjustment signal. Therefore, for all transmission data frames received by the input terminal 10, the fourth
As shown in Figure E, it can be output as a transmission data frame with a constant level.

That is, even if different transmission data frames are transmitted by m and n stations, they can be received as transmission data frames of a constant level without a pre-angle code.

Although not shown, the output of the variable gain amplifier 14 is a simple digitization circuit (for example, a comparator circuit, etc.)
The signal enters the demodulation circuit through the signal and is demodulated here.

Further, the gain of the variable gain amplifier 14 cannot be varied without limit, but is saturated with a gain that sufficiently amplifies the lowest signal level to remove noise.

Next, FIG. 5 shows an example in which a variable threshold comparator 15 is used in place of the variable gain amplifier 14.

This case is also the same as that shown in FIG. 3, but the comparison signal D' of the integrating circuit 13 becomes as shown by the dotted line in FIG.

As detailed above, according to the present invention, a transmission data frame and a transmission data frame obtained by delaying the transmission data frame are combined by an OR circuit and outputted as a combined transmission data, and Since this combined transmission data is used to create the gain adjustment signal for the variable gain amplifier or the comparison signal for the variable threshold comparator, the pre-angle code that is essentially unnecessary can be removed.

Therefore, a circuit for creating a pre-angle code and removing this code on the receiving side is not required in the data transmission device, and the entire system can be simplified, and can be easily implemented using a dedicated LSI.

This eliminates the hassle of actual design, and has great practical value.

Furthermore, by using a combinational transmission data frame, it is possible to create gain adjustment signals etc. as data that extends the original transmission data frame, covering all transmission data frames and adjusting the gain in a stable state. A table where adjustments etc. can be made.
data receiving device.

[Brief Description of the Drawings] Fig. 1 is a configuration diagram of a conventional device, Fig. 2 is a signal waveform diagram explaining the operation of the device shown in Fig. 1, and Fig. 3 is an implementation of the data receiving device according to the present invention. FIG. 4 is a signal waveform diagram illustrating the operation of the device of the present invention, and FIG. 5 is a configuration diagram showing another example of the device of the present invention.

Claims (1)

[Scope of utility model registration request] In a data receiving device that controls a variable gain amplifier or a variable threshold comparator according to a reception level of transmission data and receives the transmission data at a predetermined level, the transmission data is provided at an input end of the variable gain amplifier or comparator. - a delay circuit that delays the image transmission data for a predetermined period of time, and an OR circuit that receives the transmission data and the transmission data delayed and output by the delay circuit, and outputs combined data that is a combination of these image transmission data; and a circuit for creating a gain adjustment signal for the variable gain amplifier or a comparison signal for the comparator using the combination data output for a long time by combining the image transmission data by the OR circuit. data receiving device.