Power control based fast convergence adaptive method in internet connection sharing (ICS) repeater

Abstract

The invention discloses a power control based fast convergence adaptive method in an internet connection sharing (ICS) repeater. The method has the following advantage: an adjustable attenuator is installed behind a power amplifier of the repeater to control the output power. A power adjusting process comprises the following steps: (1) in the initial phase of echo cancellation, maintaining the attenuation value of the attenuator at the maximum betamax; (2) after maintaining the attenuation value at the maximum betamax for T1, gradually reducing the attenuation value, and adjusting the attenuation value by the attenuator once every T; and (3) when the attenuation value of the attenuator is adjusted to the minimum betamin, causing the power output of the repeater the reach the maximum and the system to enter into the stable working state. By the method disclosed by the invention, the transmitting power control technology can be introduced into the digital terrestrial television repeater, and is combined with the adaptive echo interference suppression technology, thus improving the convergence speed of the adaptive echo interference algorithm and effectively reducing the self-excitation risk of the repeater.

Description

technical field [0001] The invention relates to a repeater of a terrestrial digital television broadcasting system, in particular to a fast convergence and self-adaptation method based on power control in an ICS repeater. Background technique [0002] With the promulgation of the digital terrestrial television broadcasting (Digital Terrestrial Television Broadcasting, DTTB) standard in China, its networking mode and signal coverage gradually become a topic of concern. In order to improve the coverage of the television network, a digital television single frequency network (Signal Frequency Network, SFN) is generally used as a networking mode. SFN has the advantages of wide coverage, less interference, low power consumption, high reliability, and high spectrum utilization. [0003] Due to various reasons, it is usually impossible for SFN to achieve seamless coverage. For weak signal areas and some remote areas or blind areas with a small number of users, the cost of setting...

AI Technical Summary

Problems solved by technology

For the method of estimating the echo channel by training sequence, the process of generating the training sequence is relatively complicated and requires a large amount of hardware resources; in addition, since the update of the filter weight depends on the sending of the training sequence, if the interval between sending the training sequence is too long, its The weight update speed may not be able to track the changes of external channels

However, in the initial stage of echo cancellation, due to the large error of the channel estimation of the repeater, the echo signal is still large, and the isolation between the transmitting and receiving antennas is small, which will bring the risk of self-excitation to the system, while the traditional The repeater does not have this measure to prevent the initial self-excitation of the repeater

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