JPH03101315A - Automatic switching system for coding system - Google Patents

Abstract

PURPOSE:To attain management with the same unit in spite of the coding system of a device on an opposite-side by permitting an A-law system to automatically discriminate a coding system from a mu-law system and executing coding and decoding by means of the appropriate coding system. CONSTITUTION:An A-law coding circuit 1 and a mu-law coding circuit 2 convert analog signals inputted to an analog signal input terminal 8 into digital signals and a coding system selection circuit 5 selects the digital signals coded by the appropriate coding system. Then, the signals are outputted to a digital signal output terminal 9. An A-law decoding circuit 3 and a mu-law decoding circuit 4 respectively convert the digital signals inputted to a digital signal input terminal 10 into the analog signal. A decoding system selection circuit 6 selects the analog signals decoded by an appropriate decoding system and outputs them to an analog signal output terminal 11. Thus, the same unit attains management in spite of the system of the device on the opposite-side.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic switching method for encoding methods that is compatible with a plurality of encoding methods.

[Conventional technology]

Conventional encoding methods include the European A-1aW recommended by CCITT and the Japanese and North American μm1aw.
are mainly adopted. However, these two systems cannot be connected to each other, and can be opposed only by circuits that perform encoding and encoding using the same rules.

Therefore, there were separate subscriber circuits, trunk circuits, and terminals corresponding to each encoding method.

[Problem to be solved by the invention]

The conventional encoding methods mentioned above include A-1aw and μmla.
w, and the encoding methods adopted often differ depending on the country. Therefore, in international call circuits between countries that have adopted different encoding methods, 2.
This poses a problem in that it is economically burdensome because it is necessary to prepare equipment for different encoding systems, and it is not possible to use them interchangeably.

[Means to solve the problem]

The automatic switching method of the encoding method according to the present invention is configured to include encoding and encoding method means for performing encoding and encoding method using an appropriate encoding method according to the day output.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

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

The analog signal input terminal 8 is connected to the A-1aw encoding circuit and μ
-1aw encoding times F! It is connected to @2. A-1a
The outputs of the w encoding circuit 1 and the μ-1aw encoding circuit 2 are
It is connected to the encoding method selection circuit 5. The output of the encoding method selection circuit 5 is connected to a digital signal output terminal 9. The digital signal input terminal 10 is connected to the A-1aw decoding circuit 3, the .mu.mlaw decoding circuit 4, and the encoding and encoding method determining circuit 7. The outputs of the A-1aw decoding circuit 3 and the μmlaw decoding circuit 4 are connected to a decoding method selection circuit 6. The encoding and encoding method determining circuit 7 has its output connected to the encoding method selecting circuit 5 and the decoding method selecting circuit 6.

Next, the operation will be explained.

The encoding and encoding method discrimination circuit 7 that receives the signal from the digital signal input terminal 10 determines that the input signal is A-1a.
It determines whether it is w or μmlaw, and outputs the determination result to the encoding method selection circuit 5 and the encoding method selection circuit 6. The analog signal input to the analog signal input terminal 8 is A-1.
The aw encoding circuit 1 and the μ/law encoding circuit 2 convert the digital signals into digital signals, and the encoding method selection circuit 5 selects the digital signals encoded with the appropriate encoding method and outputs them to the digital signal output terminal 9. Output.

Further, the digital signal input to the digital signal input terminal 10 is converted into an analog signal by the A-1aw decoding circuit 3 and the μ-1aw decoding circuit 4, respectively, and the decoding method selection circuit 6 selects the appropriate decoding method. The decoded analog signal is selected and output to the analog signal output terminal 11.

FIG. 2 is a block diagram of a second embodiment of the invention.

The analog signal input terminal 105 is connected to an A-1aw or μmlaw encoding circuit 101 that is made using conventional technology and has a function of either the A-1aw method or the μ-1aw method. A-1aw or μ-1aw encoding circuit 1
The output of 01 is connected to a digital signal output terminal 106 via a digital signal format conversion circuit 103 having a mutual exchange function between the A-1aw format and the μ-1aw format.

The digital signal input terminal 107 is connected to a digital signal format conversion circuit 103 and an encoding and encoding format determination circuit 104 that determines the encoding format of the digital input signal. The output of the encoding and encoding method determining circuit 104 is connected to the digital signal method converting circuit 103. The digital input signal is an A-1aw signal created using conventional technology via the digital signal format conversion circuit 103.
The output of the 8m1aw decoding circuit 102 is connected to an analog signal output terminal 108.

Next, the operation will be explained.

The encoding and encoding method determination circuit 104 that receives the signal from the digital signal input terminal 107 determines that the input signal is A.
-1aw system or μmlaw system is determined, and the determination result is output to the digital signal system conversion circuit 103. The A-1aw or μ-1aw encoding circuit 101 that receives the analog signal input to the analog signal input terminal 105 converts the analog signal into a digital signal of a predetermined format, and then converts the analog signal into a digital signal of a predetermined format. The digital signal is converted into an appropriate digital signal according to the determination result previously received from the encoding/encoding method determination circuit 104 and output to the digital signal output terminal 106 . Further, the digital signal format conversion circuit 103 that receives the digital signal input to the digital signal input terminal 107 converts the received digital signal into a digital signal of a predetermined format, and then performs A-1aw or 8m1aw decoding. circuit 102
converts it into an analog signal, and outputs it to the analog signal output terminal 108.
Output to.

〔Effect of the invention〕

As explained above, the present invention is based on the A-1aw method or the μ-1
By automatically determining the encoding method (AW or AW) and performing encoding using the appropriate encoding method, the same device can be used regardless of the encoding method of the other party's device. There is.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a first embodiment of the invention, and FIG. 2 is a block diagram of a second embodiment of the invention. 1...A-1aw encoding circuit, 2...μ-1aw encoding circuit, 3...A-1aw decoding circuit, 4...μ
-1 aw decoding circuit, 5... encoding method selection circuit, 6
...Decoding method selection circuit, 7,104...Encoding and encoding method discrimination circuit, 8,105...Analog signal input terminal, 9,106...Digital signal output terminal, 10.107 ...Digital signal input terminal, 11.
108...Analog signal output terminal, 101...A
-1aw or μmlaw encoding circuit, 102-...A-
1aw or μm1aw decoding circuit, 103...Digital signal system conversion circuit.

Claims (1)

[Claims] It is characterized by having a discriminating means for receiving a digital signal and automatically discriminating the encoding method of the digital signal, and an encoding and decoding means for encoding and decoding with an appropriate encoding method according to the output of the discriminating means. An automatic encoding method switching method.