mohatta2015.pdf
signal processing from power amplifier operation control point of view
signal processing from power amplifier operation control point of view
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PROBLEMS 67<br />
b) What is the detected value of «i?<br />
c) What is the value of z 2 with ZF DFE?<br />
d) What is the detected value of s 2 ?<br />
3.2 Suppose the received samples can be modeled as r\ = 2s\ + so + n\ and<br />
r 2 = 2s 2 + «i + n 2 . Also, s ( , = +1, r\ — 3.1, and r 2 = —1.01. The noise power is<br />
σ 2 = 0.1.<br />
a) Using ZF DFE, what are the detected values for s\ and s 2 ?<br />
b) Do you think the detected values are correct? Why?<br />
c) Suppose the noise power is σ 2 = 100. Do you think the detected values<br />
are correct?<br />
3.3 Suppose the received samples can be modeled as T\ = 2s\ + s» + n\ and<br />
r 2 — 2s 2 + si + n 2 . Also, σ 2 = 10, s () = +1, Γχ = 8, and r 2 = -20.<br />
a) Using ZF DFE, what are the detected values for si and s 2 ?<br />
b) Do you think the detected values are correct? Why?<br />
More details<br />
3.4 Consider the MIMO scenario in which c = 10, d = 7, e = 9 and / = 6.<br />
a) What is the matrix A that triangularizes the channel while maintaining<br />
the noise power?<br />
b) What is the matrix C that is the new channel matrix?<br />
c) If ri =9 and r 2 = 11, what is the detected value for s\ using triangularization?<br />
d) Using ZF DFE, what is the detected value for s 2 ?<br />
3.5 For the general dispersive scenario, determine the SINR lower bound when a<br />
decision error is made.<br />
3.6 For the general MIMO scenario, determine the SINR lower bound for s 2 when<br />
a decision error is made on S\.<br />
3.7 For the general MIMO scenario, suppose we want to detect s 2 first, instead<br />
of s\.<br />
a) If we first replace r\ with yi = n — pr 2 , what should g be set to make t/i<br />
independent of s\l<br />
b) What is the resulting noise u\ in terms of n\ and n 2 ?<br />
c) If we then replace r 2 with j/ 2 = r 2 + hr\, what should h be set to so that<br />
the resulting noise is uncorrelated with u\ ?<br />
d) What is the resulting channel matrix C?<br />
The math<br />
3.8 For the general dispersive SC6n&riO [Vrn — £^m -r dSm — \ + n m ), determine the<br />
input SNR such that MF and ZF DFE have the same performance (same output<br />
SINR),<br />
a) assuming the ZF DFE makes no decision errors.