Malong Wang Ting-change Performance Analysis and Simulations of UWB PAM Communications In AWGN Channel Malong Wang Ting-change 8/7/2019 Inha Telecom. Lab.

Name of Journal or Conference 2004 4th International Conference on Microwave and Millimeter Wave Technology Proceedings @2004 IEEE 8/7/2019 Inha Telecom. Lab.

Objectives Deduces the theory of BER for PAM end-to-end communications in AWGN channel Analyzes the BER curves and draws out the conclusions about optimum non-bipolar PAM signal and about the superiority of bipolar PAM signal It validates the theoretical prediction through simulations 8/7/2019 Inha Telecom. Lab.

Contents Introduction BER Formula for non-bipolar PAM Signal BER Formula for bipolar PAM signal Analysis of BER Figures Simulation Results Conclusion 8/7/2019 Inha Telecom. Lab.

Introduction There are two basic methods to produce UWB signals: to make use of OFDM in producing a GHz signal (2) directly produce a pulse, and this pulse’s duration is only in the level of nanosecond (IR Radio Technology) 8/7/2019 Inha Telecom. Lab.

Introduction The UWB technology based on nanosecond impulse has been widely concerned in military applications because of its LPDD (low probability of detection/interception), very high data rate and low power consumption There are two primary ways to realize the modulation of information: PAM (pulse amplitude modulation) and PPM (Pulse position modulation) 8/7/2019 Inha Telecom. Lab.

Introduction Since the capability and quality of end-to-end communications between radios are major considerations in military communications This paper focuses on end-to-end communications adopting binary UWB-PAM signals 8/7/2019 Inha Telecom. Lab.

BER Formula for non-bipolar PAM Signal The pulse shapes of s0(t) and sl(t) are the same, and the energy of %(t) is l/k of sl(t)'s In AWGN channel, a matched filter maximizes the output signal-to-noise ratio (SNR) and probability density of signals outputted by matched filter are 8/7/2019 Inha Telecom. Lab.

BER Formula for non-bipolar PAM Signal When pp(r|s1,)> (1-p) p(r|s0), we decide S1 as the transmitted signal; when pp(r|s1,)< ( 1 -p) p(r|So), we decide s0 as the transmitted Assuming the decision threshold is b then pp(b|s1)=(1-p)p(b|s0) ……….(4) 8/7/2019 Inha Telecom. Lab.

BER Formula for non-bipolar PAM Signal Normalizing the sl(t), i.e. to make Eb=1. And assume “0”,”1” of the original data are equally probable a priori, i.e. p=0.5. We can express (5) as (6) 8/7/2019 Inha Telecom. Lab.

BER Formula for non-bipolar PAM Signal Given that sl(t) was transmitted, the probability of error is: 8/7/2019 Inha Telecom. Lab.

BER Formula for non-bipolar PAM Signal Similarly, given that s0(t) was transmitted the probability of error is 8/7/2019 Inha Telecom. Lab.

BER Formula for bipolar PAM Signal Assuming transmitter will produce a impulse signal s1(t) if there is a digital “1”, and will produce a impulse signal s0(t) if there is a digital “0” The probability of sl(t) is p, and the probability of s0(t) is 1-p, the pulse shapes of s0(t) and sl(t) are the same, and s0(t)=-sl(t). Then, (1) (3) (5) (6) (7) transform into (1O) (11) (12) (13) (14) respectively 8/7/2019

BER Formula for bipolar PAM Signal 8/7/2019 Inha Telecom. Lab.

Analysis of BER Figures 8/7/2019 Inha Telecom. Lab.

Analysis of BER Figures 8/7/2019 Inha Telecom. Lab.

Simulation Results 8/7/2019 Inha Telecom. Lab.

Simulation Results 8/7/2019 Inha Telecom. Lab.

Conclusion Non-bipolar PAM will be optimum if SNR is around 10 dB In general the bipolar PAM signal is superior to the non-bipolar PAM signal The tendency of UWB-PAM BER is predicted and the validity of this prediction is validated through simulations 8/7/2019 Inha Telecom. Lab.

THE END 8/7/2019 Inha Telecom. Lab.

Pulse Amplitude Modulation (PAM) Amplitude of periodic pulse train is varied according to the message signal m(t) Digital PAM: coded pulses of the sampled and quantized message signal are transmitted (next slide) Analog PAM: message signal is sampled every Ts seconds (symbol period) and held for T seconds t Ts T T+Ts 2Ts p(t) t m(t) Ts T T+Ts 2Ts s(t) m(0) m(Ts) Pulse shape is rectangular pulse See lecture 12 8/7/2019

Pulse Amplitude Modulation (PAM) Transmission on communication channels is analog One way to transmit digital information is called 2-level digital PAM receive ‘0’ bit Tb -A ‘0’ bit t Tb -A Additive Noise Channel input output x(t) y(t) receive‘1’ bit Tb t A ‘1’ bit Tb t A How does the receiver decide which bit was sent? 8/7/2019

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Explanation 8/7/2019 Inha Telecom. Lab.