Very High-Performance Echo Canceller for Digital Terrestrial Television in Single Frequency Network

Abstract

The principal aim of this paper is to cancel out the natural and man-made echoes in single-frequency networks (SFN). The challenge is to detect and remove feedback echoes and enhance the intelligibility of the essential parameters in SFN of digital terrestrial television broadcasting (DTTB) transmitter systems, especially the Modulation Error Ratio (MER), with optimizing coverage areas. We suggest a Digital Video Broadcasting (DVB) gap filler (GF) with two types of echo cancelling: Digital Adaptive Equalizer (DAE) and Doppler Enhanced Echo Canceller (DEEC). The proposed GF outperforms standard GF (SGF), finite impulse response filter (FIR GF), and adaptive GF (AGF) techniques by 33%, 17%, and 13%, respectively. Furthermore, the obtained MER makes the proposed GF (PGF) ideal for operating in SFN using Coded Orthogonal Frequency Division Multiplex (COFDM) technique.

Sistema Gap Filler assistido por Rádio sobre Fibra

“…Este problema é causado pelo acoplamento de ondas entre a antena receptora e retransmissora. Para combatêlo, algumas estratégias são tipicamente utilizadas: uso de antenas com elevada relação frente-costa; isolação das antenas de recepção e retransmissão, embora estas sejam comumente instaladas na mesma torre de telecomunicações; uso de cadeias de processamento digital de sinais (DSP) e filtros no equipamento de rádio repetidor, ainda que a complexidade do mesmo aumente ao incorporar a funcionalidade "cancelador de eco" [2][3][4][5][6]. Entretanto, mesmo com o emprego das estratégias citadas, há degradação significativa do parâmetro modulation error ratio (MER) na estação repetidora, o que limita o desempenho do sistema em questão.…”

A Survey on Error–Correcting Codes for Digital Video Broadcasting

“…The biggest strength of this system is the use of the concatenated codes, which can deliver dramatically clear and error-free. It can also succeed in the broadcast of successful simultaneous high sound quality and video signal transmissions by effectively correcting errors that occur from echo interferences, especially in Single Frequency Network (SFN) [12,13] Our ambition for such an overview is threefold. First, most comprehensive books on ECC do not even reveal suitable ECCs in a specified domain such as DVB, and there is very little work published, like [14] or they treat DVB systems separately with DVB overall transmission sequence.…”