Proceedings of the KIEE Conference (대한전기학회:학술대회논문집)
- 1988.07a
- /
- Pages.179-182
- /
- 1988
Weighted QPSK/PCM Speech Signal Detection with the Erasure Zone
가중치를 부여한 QPSK/PCM 음성신호의 소거대역 설정에 의한 신호수신
- Ahn, Seung-Choon (Korea Telecommunication Authority, Chonbuk National University) ;
- Lee, Moon-Ho (Korea Telecommunication Authority, Chonbuk National University)
- Published : 1988.07.01
Abstract
Since the bits in any encoded PCM word are of different importance to the bit positions, in order to improve the signal to noise ratio the technique that the encoded signal bits are weighted for the QPSK transmission system, is presented. Also the erasure zone is established at the detector, such that if the output falls into the erasure zone, the regenerated sample is replaced by interpolation. Two weighting methods are shown here. One is the method that the same weighting profile is used to Q and I dimension in QPSK signal constellations. The other is diferent weighting to Q and I dimension. The gains of this new technique in overall signal s/n compared to conventional QPSK transmission system were 5 db and 2db, respectively.
Keywords