PAPR Reduction of TD-SCDMA Using Joint Transmission Technique

摘要

Current downlink TD-SCDMA system uses Joint Detection (JD) technique to reduce interference. How­ever, the technique needs significant calculation and channel estimator in mobile station (MS). Using TDD features where received uplink channel impulse responses (CIRs) can be used in downlink, Joint Transmission (JT) has been proposed. In JT, all of JD functions are removed into base station (BS), realizes a simple MS. However, studies of JT show that the JT increases transmission power. This may affect Peak to Average Power Ratio (PAPR) of the system. For a single path case, our result shows that JT increases overall transmitted power as well as average transmitted power, leading to lower PAPR. However, as JT multiplies CIRs with spreading codes before transmis­sion, high PAPR might be occurred in multipath case. In this paper a new approach of JT is proposed to achieve low PAPR in multipath case. The performance evaluation is done using computer simulation.