JPH02205129A - Frame checking sequence system - Google Patents

Abstract

PURPOSE:To prevent a frame from being identified erroneously without attaching frame checking sequence on the tail end of the frame by attaching the frame checking sequence only on a specific part in the frame. CONSTITUTION:An audio frame 2 is inputted to an audio/nonaudio identification circuit 5, and inputted to a frame checking sequence attaching circuit 10 for audio, and furthermore, an output frame 7 is outputted. On the output frame 7, the frame checking sequence 6 for an audio display part 1 in the frame is attached, and no frame checking sequence is attached on the tail end. Meanwhile, a nonaudio frame 3 is inputted to the audio/nonaudio identification circuit 5, and inputted to a frame checking sequence attaching circuit 11 for nonaudio. And the frame checking sequence 8 for the whole of the frame is attached on the final part of an output frame 9 from the frame checking sequence attaching circuit 11 for nonaudio.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a frame check sequence method in which a frame check sequence is attached to a frame as a transmission unit and then transmitted.

[Prior Art] Conventionally, in a frame check sequence method, a frame check sequence method is used to check the frame check sequence for the entire frame.
Executes a check operation and inserts a frame at the end of the frame.
A check sequence was added to the frame, and some frames were transmitted without a frame check sequence added to the end of the frame. for example,
When voice is packetized and mixed with other non-voice data packets and transmitted over a line, voice and non-voice are distinguished by the value of a specific part within the frame. Error control is performed by a frame check sequence added to the end of the frame.For audio packets, on the other hand, to avoid audio delays, either no frame check sequence is added to the end of the frame, or no frame check sequence is added at the end of the frame. Even if it was, there was no error control using it.

[Problem to be Solved by the Invention] However, in the past, in order to avoid audio delay in audio packet frames, a frame check sequence was not added at the end of the frame, or was added at the end of the frame. Since there is no error control at all, the specific part that distinguishes between voice and non-voice within the frame is destroyed by line noise and is mistakenly identified as a voice packet, reducing the quality of the voice. There were drawbacks.

Therefore, an object of the present invention is to eliminate erroneous frame identification without adding a frame check sequence to the end of the frame.

[Means for Solving the Problems] Technical means of the present invention for solving such problems is a frame check sequence that adds a frame check sequence to a frame as a transmission unit and transmits the frame. Among the sequence methods, there is a frame check sequence method in which a frame check sequence is assigned only to a specific part within a frame.

[Embodiment] Hereinafter, a frame check sequence method according to an embodiment of the present invention will be described based on the accompanying drawings.

The frame check sequence method according to this embodiment packetizes voice, mixes it with other non-voice data packets, and transmits it to the line. In this embodiment, as shown in FIG. 1, an audio frame 2 as a transmission unit has an audio display 1 set in a specific part within the frame.

Furthermore, in the non-voice frame 3 as a transmission unit, a non-voice display 4 is set in a specific part within the frame. Furthermore, in this embodiment, voice frame 2 and non-voice frame 3
The speech/non-speech discrimination circuit 5 is provided with a speech/non-speech discrimination circuit 5 to which the speech/non-speech is input. Also, a frame check sequence adding circuit 10 for audio adds a frame conflict check sequence 6 to the audio display section 1 in the audio frame 2 outputted from the audio/non-speech identification circuit 5, and outputs it as an output frame 7.
It is equipped with Then, a frame check sequence 8 is added to the end of the non-voice frame 3 for the entire non-voice frame 3 output from the voice/non-voice identification circuit 5, and a non-voice frame is output as an output frame 9. A check sequence providing circuit 11 is provided.

Therefore, according to the frame check sequence method according to this embodiment, the voice frame 2 is input to the voice/non-voice discrimination circuit 5, and then input to the voice frame check sequence providing circuit 1o. . An output frame 7 is output from the audio frame check sequence providing circuit 10. This output frame 7 includes frame check information regarding the audio display section 1 within the frame.
Sequence 6 is added, and no frame check sequence is added at the end of the one-way speech frame 3. By inputting it to the speech/non-speech discrimination circuit 5,
Non-voice frame check sequence provision circuit 11
is input. Then, the non-voice frame check
The output frame 9 from the sequencer circuit 11 has a frame check sequence 8 for the entire frame.
is added to the mttt tail of the frame.

Therefore, for non-voice data packets, the frame check mark added to the end of Ik of output frame 9 is
Sequence 8 performs error control. On the other hand, for audio packets, since no frame check sequence is added to the output frame 7, audio delays can be avoided. Furthermore, since the frame check sequence 6 is added to the audio display 1 of the output frame 7, it is possible to prevent the audio display 1 from being destroyed by line noise or the like and being erroneously identified.

[Effects of the Invention] As explained above, according to the frame check sequence method of the present invention, by assigning a frame check sequence only to a specific part within a frame,
For example, it is possible to perform a frame check only on a specific part for distinguishing frames such as audio/non-audio frames, thereby avoiding misrecognition of audio packets, etc.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the structure of a frame check sequence system according to an embodiment of the present invention. 1: Voice display 2: Voice frame 3: Non-voice frame 4: Non-voice display 5 2. Voice/non-voice identification circuit 6: Frame book check sequence 7: Voice frame 8: Frame check sequence 9: Non-voice frame 10 :Voice frame check sequence provision circuit 11:Non-voice frame check sequence provision circuit

Claims (1)

[Claims] In a frame check sequence method in which a frame check sequence is attached to a frame as a transmission unit and the frame is transmitted, the frame check sequence method is characterized in that a frame check sequence is attached only to a specific part within the frame. Check sequence method.