1. The Derivation of a BER ExpressionIn this section, the BER performance of the impacting filter based EBPSK receiver is analyzed in an AWGN channel.The EBPSK modulated waveform corresponding to ��0�� is a pure sine wave, after passing the AWGN channel and the special impacting filter at the receiver, then the envelope r0 of the filter output Ruxolitinib mw is with Rice distribution [11], whose probability density function (pdf) [12] is as follows:p(r0)=r0��2exp(?r02+A022��2)?I0(r0A0��2)(4)where A0 is the amplitude of the filter output, ��2 the noise variance, and I0(z) the zero-order modified Bessel function, defined as follows:I0(z)=��n=0��z2n22n?n!?n!(5)A similar analysis can also be done aiming at code ��1��. If we only consider those periods with phase jumping during ��, the jumping information can be transformed into parasitic amplitude information after receiving filter, i.
e., producing the higher amplitude impulse. At this time, its envelope r1 still is Rice distribution, the corresponding pdf is:p(r1)=r1��2exp(?r12+A122��2)?I0(r1A1��2)(6)This Inhibitors,Modulators,Libraries derivation of the BER is based on the special and linear impacting filter as given in Figure 2, which can produce the amplitude impulse at the point Inhibitors,Modulators,Libraries of the phase jumping corresponding to code ��1�� that is much higher than the background of code ��0��, i.e., A1 > A0.
Let A1 = A0 + ��A = A0 + kA0 Inhibitors,Modulators,Libraries and k > 0Therefore, assuming that code ��0�� and ��1�� be transmitted with equal probability and the decision threshold be UT, then the BER of the EBPSK system should be:Pe-EBPSK=12[P(1|0)+P(0|1)]=12[��UT�� p(r0)dr0+��?��UT p(r1)dr1]=12[��UT��r0��2exp(?r02+A022��2)?I0(r0A0��2)dr0+��?��UTr1��2exp(?r12+A122��2)?I0(r1A1��2)dr1]=12[1?F0(uT)+F1(uT)]=12[1+Q1(A0��,UT��)?Q1((1+k)A0��,UT��)](7)where Inhibitors,Modulators,Libraries F0(x) and F1(x) is cumulative distribution function of Ricean random variable r0 and r1, respectively, and Q1(a,b) is Marcum��s fuction, defined as follows:Q1(a,b)=e?(a2+b2)/2��k=0��(ab)k Ik(ab)(8)3.2. Calculation of the Parameters in the BER FormulaWe will now discuss in detail how to ascertain the parameters A0, k, ��2 and UT in the BER formula (7) in this subsection.(1) The amplitude A0 is evaluated as follows:In EBPSK modulation and via Fourier transform:g0(t)=A sin wct?FG0(w)=A��j[��(w?wc)?��(w+wc)](9)Let the frequency response of the filter be H(w), then the signal filtered in frequency domain can be written as:Y0(w)=G0(w)?H(w)=A��j[��(w?wc)?��(w+wc)]?H(w)=A��j?H(wc)?��(w?wc)?A��j?H(?wc)?��(w+wc)(10)So the waveform in time domain is:y0(t)=F?1[Y0(w)]=A2j[H(wc)?ejwct?H(?wc)?e?jwct]=A2j[|H(wc)|?ej(wct+��1)?|H(?wc)|?e?j(wct?��2)](11)where Brefeldin_A 1 = H(wc), 2 = H(?wc).
The impacting filter has conjugate zero points selleck and poles, so 1 = ?2, and |H(wc)| = |H(?wc)|, then the received signal after filter is as follows:y0(t)=|H(wc)|?A sin (wct+��1)(12)So A0 = A ? |H(wc)|, A1 = (1+k) ? A ? |H(wc)|, and in accordance with Eq.(3), let A=2EbT.