In wireless communications has one characteristic that is the phenomenon of multipath fading, it takes a technology that could make the reflection signal does not eliminate the primary signal. The use of multiple antennas at the transmitter and the receiver is expected to result in improved quality of the wireless communication service. This technique is known as MIMO (Multiple Input Multiple Output). One scheme is MIMO STBC (Space Time Block Code), which has a subclass of OSTBC (Orthogonal Space Time Block Code). The principle OSTBC is sending some signal replicas information on the independent channel fading in orthogonal signal format, so that at least one signal receiver who did not experience the worst fading. So with the process of sending data faster and more reliable. At the end of this project described the performance of OSTBC using 4 pieces with rate ½ and ¾ to resolve an issue with multipath fading in wireless communications. Here is observed the SNR (Signal To Noise Ratio) and BER (Bit Error Rate) that can be know performance. Results obtained in the form of graphs of functions of Eb / No in dB. For OSTBC rate ½ 4 QAM modulation for the amount of 4 antenna transmitter and receiver antenna gain BER 10ିଷ at SNR ± 9 dB, for 8 QAM modulation at ± 8 dB SNR for 16 QAM modulation on the SNR ± 7 dB. For OSTBC rate ¾ 4 QAM modulation amount of 4 antenna transmitter gain 4 antenna receiver BER ¾ at SNR ± 12.5 dB, for 8 QAM modulation at ± 12 dB SNR for 16 QAM modulation on the SNR ± 11 dB Keywords : Multipath fading, OSTBC, rate,MIMO
展开▼
