Capacity Improvement with DFC in QAM-CDMA
نویسنده
چکیده
The use of Code Division for Multiple Access or CDMA is well established. We know that it has advantages in multipath environment and increase in capacity due to sectoring antenna and voice activity factor. Here a step by step comparison is made among Frequency Division Multiple Access, Time Division Multiple Access and Code Division Multiple Access when capacity or SNR is of main concern. A design of downlink and uplink CDMA along with Decision Feedback Cancellation Scheme and BCH coding is given to achieve lowest noise variance among competing CDMA design. To reduce channel outage due to excess Multiple Access Interference, a double six adjacent cells using two different frequencies in CDMA is proposed.
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