Method for cutting out realtime multipath fax

Abstract

A method for intercepting multi path fax in real time comprises the main control unit, the relay interface unit, the digital time division unit, the audio processing unit and the fax intercepting unit. Connects the up and down stream data relative to the user monitored and calling to the relay interface unit; makes connection to the audio processing unit; the audio processing unit makes linear overlap for the up and down stream data, then output digital time division switching unit; the main control unit controls the digital switching unit to make connection for the overlapped linear data outputted by audio processing unit to the fax intercepting unit, and orders the fax intercept unit to start to intercept the fax; the fax intercepting unit starts to transmit data.

Description

technical field [0001] The invention relates to a method for intercepting multi-channel faxes in real time, which belongs to the communication field. In particular, it relates to a method for realizing real-time interception of multi-channel user faxes by using digital modulation and demodulation (MODEM) technology. Background technique [0002] With the rapid development of communication technology, the application of fax machines has been quite popular. Faxes can be sent wherever there is a telephone. Compared with the telephone, the fax has the characteristics of intuitive image and good confidentiality. It plays a more important role in people's daily life. It plays an increasingly important role, and the important information of a large number of users is sent to each other by fax. For some special departments, such as public security organs, national security organs, customs and other departments, it is sometimes necessary to intercept user faxes without being perceiv...

AI Technical Summary

Problems solved by technology

This method is inflexible, and every time a user is changed, the connection must be reconnected, which wastes resources. When the user does not send a fax, the receiving device cannot be used for other users who need to intercept the fax, and it is not convenient for the management of user data.

[0004] With the rapid development of semiconductor technology, multi-channel digital modulation and demodulation MODEM chips are more and more widely used, and the cost is getting lower and lower. However, they are mostly used for data and fax storage and forwarding. If they are used for fax interception, the following problems exist : 1) Theoretically speaking, the digital MODEM chip can obtain fax information as long as it receives the sender’s data, but it is impossible that there is no echo in the actual switch system, that is, the receiver’s data is reflected back to the sender’s time slot through the subscriber line. The data interferes with the normal reception of the MODEM chip, making it difficult to intercept the fax, and the echo suppressor cannot be used in the fax sending and receiving

2) The sending of the fax is carried out after the sending and receiving parties negotiate and confirm various parameters. The MODEM chip as the intercepting party cannot participate in it and can only adapt passively. It is easy to misjudgment or miss receipt, resulting in the inability to continue the interception

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