JPS63799A - Digital remote control transmitter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides information rOJ,
Regarding a digital remote control transmission device that distinguishes rlj and modulates the pulse at a specific frequency and transmits it, a check bit is added to the information bit for transmission to detect or correct errors during transmission. It is about things.

[Conventional technology]

-a-type remote control system is shown in FIG. In FIG. 2, 1 is a transmitting circuit that modulates a transmission code at a specific frequency and transmits it, 2 is a receiving circuit that processes the received signal, and 3 is an input circuit that receives the output of the transmitting circuit 1.
A light emitting section 4 is made up of a light emitting element such as a light emitting diode, and a light receiving section 4 is made up of a light receiving element such as a photodiode, which receives the optical signal a from the light emitting section 3 and sends an output to the receiving circuit 2.

In the remote control system configured in this way, first, the transmission circuit 1 encodes and modulates the information to be sent, and the light emitting section 3 converts it into an optical signal a and transmits it. Next, the transmitted optical signal a is received by the light receiving section 4, demodulated by the receiving circuit 2, and the command is decoded.

In a remote control system with such a configuration and function, the distinction between information ``rob'' and ``rlJ'' is based on bit ro.
As shown in FIG. 3, which is a pulse waveform diagram of "j, r+",
This is done by two consecutive pulse intervals. That is, in FIG. 3, the short pulse interval 5 shown in the figure (IS) corresponds to "0", and the long pulse interval 6 shown in the figure (IS) corresponds to "1".

Conventionally, a method has been adopted in which several bits of roj and rlJ are combined into one word 7 in a transmission code format as shown in Figure 4, and the type of instruction is distinguished according to the data code of this word 7. Ta. Furthermore, in order to avoid interference with other remote control systems, some bits of the transmission code may be assigned as a custom code, and the remaining bits may be assigned to the instruction code. In this case, the receiving side executes the command only when the decrypted custom code matches the code given to its own system. In FIG. 4, 8 indicates the repetition period of the transmission code.

[Problem that the invention seeks to solve]

In the conventional digital remote control method as described above, on the receiving side, rob, rl
If the judgment criteria of J are similar and the number of bits is one loss, then
It has the disadvantage that it may cause malfunction or interference, making it unusable as a remote control system.The main cause of this type of malfunction or interference is disturbance in the transmission path (9FI sound). It is.

The present invention has been made in view of these points, and its purpose is to provide a digital remote control transmission device that can reduce malfunctions and interference caused by disturbances in a remote control system, and can provide a large number of independent remote control systems. There is a particular thing.

[Means for solving problems]

In order to achieve such an object, the present invention distinguishes between information 1ron and rlJ based on the length of the two pulse intervals, and modulates a transmission code consisting of a leading pulse, a custom code, and an instruction code at a specific frequency. In this digital remote control device, a check bit for error detection or correction is transmitted following the information bit.

[Effect]

In the present invention, the code decoded on the receiving side is checked using check bits, and based on the results, errors in information bits occurring in the transmission path are detected or corrected, so malfunctions and interference caused by disturbances can be prevented. becomes less.

(Example) Hereinafter, an example of the present invention will be explained with reference to the drawings.
The figure shows a transmission format of a digital remote control transmission device according to an embodiment of the present invention. In the figure, numeral 9 is a leading pulse indicating the beginning of the transmission code, which is effective, for example, when applying AGC on the receiving side, but can be omitted if unnecessary. 10 is an information bit, and 11 is a check bit. Now, suppose we use CRCC (Cyclic Red
undancy check code; cyclic code)
We will explain the case in which this is adopted. The information polynomial that represents the information bits as a polynomial is Mfx), and the CRCC generator polynomial is G (xi, X k@M (X) is G(×)
The quotient polynomial divided by Q (X) and the remainder polynomial 2 are RfX
), the following relationship holds between these polynomials. Here, k is the number of check bits, that is, the degree of the generator polynomial.

X"-M(X)-Q(XI G(X)+RfXl
...(1) U(x)-X' ・M(x)-R(x)=Q(xl-
G(x) ·(2) is transmitted as a transmission polynomial. In FIG. 1, information bit 10 corresponds to M(X), and check bit 11 corresponds to R(X). As is clear from equation (2), the transmission polynomial U(X) can be divided by the generator polynomial 〇(X). If it is not divisible, this indicates that an error has occurred due to some disturbance in the transmission path.

Therefore, errors can be detected by dividing the receiving polynomial by the generating polynomial on the receiving side. Furthermore, by using different generating polynomials between different systems, there is a strong effect of preventing not only malfunctions but also interference between different systems. The effect is further enhanced when the information bit contains a custom code.

In addition, although the above embodiment has been described using CRCC as an example, an error correction code may be used instead of simple CRCC.

For example, if a single error correction code such as a Hamming code is employed, a single error can be corrected and a double error can be detected at the same time.

In addition, this embodiment adopts a format in which information bits and check bits are arranged separately, so if error detection is not necessary in a simple system, the check bits can be omitted; It also has excellent coexistence with simple systems.

〔Effect of the invention〕

As explained above, according to the digital remote control transmission device according to the present invention, the check bit is transmitted following the information bit, so that the receiving side can detect errors caused by disturbances on the transmission path, or This has the effect of realizing a digital remote control system with less malfunction and interference between systems.

[Brief explanation of the drawing]

Fig. 1 is a waveform diagram showing the transmission code of the digital remote control transmission device according to the present invention, Fig. 2 is a system diagram showing the -s type remote control system, and Fig. 3 is the pulse interval (bit FIG. 4 is a waveform diagram showing transmission codes for explaining the conventional digital remote control method. In the figure, 1 is a transmitting circuit, 2 is a receiving circuit, 3 is a light emitting section, 4 is a light receiving section, 5 is a pulse interval indicating "0", and 6 is a "1"
7 is a transmission code, 8 is a repetition period, 9 is a leading pulse, 10 is an information bit, and 11 is a check bit.

Claims (4)

[Claims] (1) In a digital remote control device that performs remote control by transmitting a digital signal to a controlled device, and the distinction between information “0” and “1” is made by the length of two pulse intervals, the transmission of the digital signal A digital remote control characterized in that the code consists of information bits and check bits for detecting or correcting errors that occur in the information bits during transmission, and the transmission order is the information bits and the check bits. Control transmission device. (2) The digital remote control transmission device according to claim 1, wherein the digital signal includes a head pulse indicating the head of the transmission code. (3) The information bits include a custom code for avoiding interference between different digital remote control transmission devices and an instruction code for operating the controlled device. Or the digital remote control transmission device according to item 2. (4) The digital remote according to any one of claims 1 to 3, characterized in that different digital remote control transmission devices use different generating polynomials for generating the check bits. Control transmission device.