Transmitting system, multiplexer and method for reducing power unevenness in sending machine band

Abstract

The invention provides a method used for reducing the roughness of the in-band power of the transmitter, a multiplexer and a transmission system. The information source data are encapsulated into a multiplex frame which is composed of three fields, including a multiplex frame head, a multiplex frame payload and a filling field. The method includes the procedures as follows: the filling field is filled with a random data sequence or a fixed data sequence with balance energy to ensure the data in the multiplex frame to realize balance energy after the modulation. Based on the method provided by the invention, the multiplexer and the transmission system, when the information source data are encapsulated into a multiplex frame, the filling field of the multiplex frame is filled with the random data sequence or the fixed data sequence with balance energy to reduce the fixed data sequence with unbalance energy in the information source data before the modulation of the transmission system and ensure the data in the multiplex frame to realize balance energy after the modulation; thereby, the roughness of the in-band power is improved; the damage for the transmitter is reduced and the requirement of stable operation of the system is well fulfilled.

Description

technical field [0001] The invention belongs to the technical field of mobile multimedia broadcasting, and in particular relates to a method for reducing in-band power unevenness of a China Mobile Multimedia Broadcasting (CMMB) transmitter, a multiplexer and a transmitting system. Background technique [0002] Broadcast system transmitters are quite different from mobile communication system transmitters, which is directly related to their transmission power. The transmission power of the broadcast system transmitter is usually very high, such as the transmitter of the CMMB system, etc., and its transmission power can reach up to four or five kilowatts. The transmitter of the mobile communication system, such as the transmitter of the 3G communication system, etc., usually has a lower transmission power, the maximum of which is not more than 40 watts. The large difference in transmit power leads to very different performance requirements for transmitters. One of the very ob...

AI Technical Summary

Problems solved by technology

In the existing transmitter implementation technology, when the modulation mode of the transmission signal is QPSK or 16QAM, due to the non-randomness of the filling data of the multiplexing frame input to the modulator, the source data after modulation increases the in-band power unevenness

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