An optimal gain control scheme for digital on-channel repeater with feedback interference canceller in digital terrestrial television broadcasting networks

作者：Liu Chang^*; He Miao; Xia Wei

来源：WSEAS Transactions on Communications, 2011, 10(5): 147-154.

• Digital on-channel repeater (DOCR)
• DTTB
• Feedback interference canceller (FIC)
• Least mean square (LMS) algorithm
• Oscillation

In this paper, a new gain control scheme is proposed for a digital on-channel repeater (DOCR) with a feedback interference canceller (FIC) in Digital Terrestrial Television Broadcasting (DTTB) networks. In the proposed scheme, a variable attenuator is placed behind the amplifier of the DOCR and the least mean square (LMS) adaptive algorithm is implemented in the FIC to estimate the feedback channel. The proposed scheme consists of two stages. In the first stage, the variable attenuator is fixed on a high attenuation level for a sufficient time with the purpose of avoiding oscillation at start-up of the DOCR. In the second stage, based on the non-oscillation condition derived in Section II, the attenuation level can be decreased at intervals until the aimed gain is approached. Simulations show that the proposed scheme increases the convergence speed of the adaptive algorithm and saves the adjusting time of approaching the aimed gain compared with the conventional gain control scheme.

• 出版日期2011
• 单位电子科技大学