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A Hybrid Multi-User Detector for CDMA Systems

M. Ranga Rao, Dr. B. Prabhakara Rao


Multi user detection is one of the most important processes in code division multiple access (CDMA) for detecting signals by multiple users. There are different MUD techniques in CDMA. In most of the methods, they detect the desired users’ signals however interference occurs and also there are chances of losing the signal. By considering these drawbacks, a new MUD technique using elliptic curve cryptography is proposed. The technique mainly intends to obtain/detect the desired user’s signal with less interference ratio. Prior to transmit the signal, an elliptic curve based key is generated. Later, the signals are encoded using the generated key and then transmitted. In the receiver, the decoding, which is an inverse operation of encoding in transmitting end, is performed in the proposed MUD technique. The decoding operation decodes only the desired user’s signal and it neglects the undesired signals. This in turn improves the performance of the MUD process of CDMA that can be validated from the obtained implementation results.


CDMA, Elliptic Curve Cryptography (ECC), Encoding, Key Generation, Multi User Detector (MUD).

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