IMPROVED PREDICTIVE POWER CONTROL OF CDMA SYSTEM IN RAYLEIGH FADING CHANNEL
| Main Authors: | Adit Kurniawan; School of Electrical Engineering and Informatics, Bandung Institute of Technology, Bandung 40132, Indonesia, Iskandar .; School of Electrical Engineering and Informatics, Bandung Institute of Technology, Bandung 40132, Indonesia, Sayid Machdar; School of Electrical Engineering and Informatics, Bandung Institute of Technology, Bandung 40132, Indonesia |
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| Format: | Article application/force-download eJournal |
| Bahasa: | eng |
| Terbitan: |
Directorate of Research and Community Engagement, Universitas Indonesia
, 2010
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| Online Access: |
http://journal.ui.ac.id/index.php/technology/article/view/488 |
Daftar Isi:
- In this paper an improved prediction-based power control is proposed for code division multiple access (CDMA)systems in Rayleigh fading channel environments. One of the most serious problems which degrades the performanceof power control algorithm is the effect of feedback delay. To overcome the effect of feedback delay, power controlneeds to employ prediction algorithm which utilises the correlation property of the past channel samples measurementsto predict the future sample values. In CDMA power control, however, the correlation property of channelmeasurements is destroyed because the transmit power is continuously updated for each power control interval. Theprediction algorithm in this paper uses the recursive least square (RLS) technique and an improved predictor algorithmis proposed to compensate for the channel correlation. The result shows that the performance of improved predictivepower control proposed in this paper evaluated in terms of bit error rate (BER) as a function of bit energy-tointerferencepower density ratio Eb/Io improved significantly from that of the conventional predictor.Keywords: CDMA, least mean square, power control, prediction, rayleigh fading