In Universal Mobile Telecommunication System (UMTS), high data rate transmission is possible by using Wideband Code Multiple Access technique (WCDMA) as an air interface. This paper studies performances of various modulation schemes such as Phase Shift Keying(both BPSK and QPSK) and 16 – Quadrature Amplitude Modulation (16-QAM) in WCDMA downlink transmission to improve its data rate. Based on Bit Error Rate (BER), performances of various modulation schemes have been investigated. The Simulation tool Matlab R2013a is used for simulation of WCDMA system implemented with QPSK, BPSK and 16-QAM modulation techniques and we are going to analysis BER vs SNR for all modulations. Performance Analysis of WCDMA on Different Modulation Techniques
1.Universal Mobile Telecommunication System (UMTS) uses Wideband Code Division Multiple Access (WCDMA) as the platform for 3G cellular network.
2.High data rate communication is possible by using WCDMA system, which results in efficient transfer of video streams and high resolution pictures to the end users.
3.It hence becomes necessary to choose a suitable modulation technique as well as error correcting mechanism to be used in WCDMA.
4.In 2G communication system Gaussian Minimum Phase Shift Keying (GMSK) is widely preferred which delivers data at the rate of 1 bit per symbol.
5.It could not deliver high data rate needed for video streaming and high resolution picture transfer, hence there is a necessity to switch over to other modulation schemes which could deliver much higher data rate.
However, implementation of modulation techniques that provide high data rate requires modulators, filters, error detecting and correcting blocks and demodulators which are quite difficult to achieve. Here performance of modulation schemes such as BPSK, QPSK and QAM are studied.
1.Simulation of Received data from two users in WCDMA system
2.Modulation and demodulation by BPSK, QPSK and 16-QAM in WCDMA system
3.Evaluation of BER vs SNR for all modulation techniques.
1.They only done evaluation of BER vs SNR for different modulation techniques.