FEEDBACK INTERFERENCE CANCELLER WITH PRE-WHITENING FILTERS
FOR ATSC EQUALIZATION DIGITAL ON-CHANNEL REPEATERS
Young-Jun Lee*, Jongwoo Shin*, Ho min Eum†, Sung Ik Park†, Heung Mook Kim† and Hyoung-Nam Kim*
*School of Electrical Engineering, Pusan National University,
San 30 Jangjeon-dong, Guemjeong-gu, Busan 609-735, Korea
hnkim@pusan.ac.kr
†Electronics and Telecommunications Research Institute,
161 Gajeong-dong, Yuseong-gu, Daejeon, 305-700, Korea
ABSTRACT
The combination of the Equalization Digital On-Channel
Repeater
(EDOCR) and
the Feedback
Interference
Canceller (FIC) may be considered as a good solution for
re-broadcasting recovered DTV signals with high power
after the reception of distorted weak signals. However, the
adoption of the FIC distorts spectrum edge which hinders
the EDOCR’s synchronization. This is because the FIC
cannot eliminate the feedback around the carrier pilot and
the edge of the spectrum clearly. To overcome this obstacle,
an FIC with the pilot-free reference (PFR) was proposed but
an additional cost for the PFR was too prohibitive to be
implemented. Therefore we propose an FIC with pre-
whitening filters (PWFs) which help the FIC estimate the
feedback channel accurately. The proposed FIC with the
PWFs eliminates the spectrum distortion clearly and
suppresses the feedback signal more powerfully with a little
additional cost compared to the FIC with the PFR.
Index Terms—DTV, EDOCR, FIC,
spectrum
distortion, pre-whitening filters
1. INTRODUCTION
Recently single frequency networks (SFNs) have been
considered for the ATSC DTV services [1-3]. Combining
the Equalization Digital On-Channel Repeater (EDOCR)
with the Feedback Interference Canceller (FIC) is an
interesting issue for organizing SFNs. Since the EDOCR
makes a high-quality of re-transmitted signal and the FIC
enhances the re-transmission signal power, the combined
system gives a near optimal solution for re-broadcasting
distorted weak DTV signals [4-9].
However, there is a cruci