• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.5
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• pp.104-108
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• 2009

In this paper, we investigate the performance of ARQ-aided downlink Time Switched Transmit Diversity (TSTD) in the WCDMA LCR-TDD system. Proposed TSTD system applies the ARQ scheme in which the receiver sends the response signal (ACK or NACK signal) to the transmitter and predicts the channel condition based on response signal after receiver checks the error, then it re-sends data. Simulation results demonstrate that the proposed TSTD scheme yields about 5.5dB performance gain, compared with the conventional TSTD in term of the frame error rate(FER) for a mobile speed of 3km/h and an FER value of 1%. In addition, 7% of throughput gain is shown when Eb/N0=7dB.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.10
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• pp.52-56
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• 2009

In this paper, we investigate the performance of the ARQ-aided downlink Time Switched Transmit Diversity (TSTD) in the WCDMA LCR-TDD system, when power ramping is applied. The proposed power ramping scheme ramps up the transmission power and then retransmits the data, when the receiver sends the response signal (ACK or NACK signal) to the transmitter and the response signal is NACK signal. Simulation results demonstrate that the proposed scheme yields about 0.7dB performance gain in terms of average Eb/N0, compared with the conventional ARQ-aided TSTD when a mobile speed is 3km/h and an frame error rate (FER) is 1%, respectively. In addition, 2.5% of throughput gain is shown when average Eb/N0 is equal to 0dB.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.12
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• pp.61-68
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• 2010

In this paper, we investigate the performance of ARQ-aided Time Switched Transmit Diversity (ARQ-TSTD) applying the multi-level control signaling in the WCDMA LCR-TDD system. Proposed ARQ-TSTD system applies the multi-level control signaling scheme in which the receiver sends the response signal (ACK or NACK signal) to the transmitter and defines NACK2 signal for multi-level control. Transmitter utilize the NACK2 control signal to the postponement of transmission and multi-user scheduling scheme proposed by this paper. Simulation results demonstrate that the proposed postponement of transmission and multi-user scheduling scheme yield about 1.3dB, 1.4dB performance gain respectively, compared with the conventional ARQ-TSTD with antenna switching scheme in tenn of the frame error rate (FER) for mobile speed of 3km/h and FER value of 10%. In addition, 14% and 11.5% of throughput gain respectively is shown when Eb/N0=-3dB.