tailieunhanh - Báo cáo hóa học: " Two-way relaying using constant envelope modulation and phase-superposition-phase-forward"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Two-way relaying using constant envelope modulation and phase-superposition-phase-forward | Tan and Ho EURASIP Journal on Wireless Communications and Networking 2011 2011 120 EURASIP Journal on . http content 2011 1 120 Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Two-way relaying using constant envelope modulation and phase-superposition-phase-forward Huai Tan and Paul Ho Abstract In this article we propose the idea of phase-superposition-phase-forward PSPF relaying for 2-way 3-phase cooperative network involving constant envelope modulation with discriminator detection in a time-selective Rayleigh fading environment. A semi-analytical expression for the bit-error-rate BER of this system is derived and the results are verified by simulation. It was found that compared to one-way relaying 2-way relaying with PSPF suffers only a moderate loss in energy efficiency of dB . On the other hand PSPF improves the transmission efficiency by 33 . Furthermore we believe that the loss in transmission efficiency can be reduced if power is allocated to the different nodes in this cooperative network in an optimal fashion. To further put the performance of the proposed PSPF scheme into perspective we compare it against a phase-combining phase-forward technique that is based on decode-and-forward DF and multi-level CPFSK re-modulation at the relay. It was found that DF has a higher BER than PSPF and requires additional processing at the relay. It can thus be concluded that the proposed PSPF technique is indeed the preferred way to maintain constant envelope signaling throughout the signaling chain in a 2-way 3 phase relaying system. Keywords 2-way relaying phase-only-forward decode-and-forward cooperative communications constant envelope modulation continuous phase modulation CPFSK discriminator detection 1. Introduction Cooperative transmission is a cost effective way to combat fading because it creates a virtual multiple-input-multipleoutput MIMO communication channel without resorting to mounting .