Standard Type ETACS Cellular NMT450 Major Mobile Radio
Standard Type ETACS Cellular NMT-450 Major Mobile Radio Standards in Europe Year of Multiple Frequency Introduction Access Band 1985 FDMA 900 MHz Modulation Channel Bandwidth FM 25 k. Hz FM 12. 5 k. Hz GMSK 200 k. Hz FM 20 k. Hz/ 10 k. Hz 4 -FSK 25 k. Hz GFSK 100 k. Hz GFSK 1. 728 MHz GMSK 200 k. Hz Cellular 1981 FDMA 450 -470 MHz NMT-900 Cellular 1986 FDMA 890 -960 MHz GSM Cellular/ PCS 1990 TDMA 890 -960 MHz C-450 Cellular 1985 FDMA 450 -465 MHz ERMES Paging 1993 FDMA CT 2 Cordless 1989 FDMA Several 864 -868 MHz DECT Cordless 1993 TDMA 1880 -1900 MHz DCS-1800 Cordless/ PCS 1993 TDMA 1710 -1880 MHz
Standard Type AMPS NAMPS USDC Major Mobile Radio Standards in North America Multiple Frequency Modulation Year Of Access Band Introduction Cellular 1983 Cellular 1992 Cellular 1991 CDPD Cellular IS-95 FDMA TDMA Cellular 1993 CDMA GSC paging 1970 POCSAG Paging 1970 1993 1994 1995 DSC-1900 (GSM) PACS PCS MIRS SMR/ PCS i. DEN Cordless 824 -894 MHz FH/ Packet Paging FM 30 k. Hz FM 10 k. Hz p/4 - DQPSK GMSK 30 k. Hz 1993 FLEX 824 -894 MHz Channel Bandwidth Simplex 824 -894 MHz 1. 8 -2. 0 GHz Several QPSK/ BPSK FSK 30 k. Hz 1. 25 MHz 12. 5 k. HZ Simplex Several 4 -FSK 15 k. Hz TDMA 1. 85 -1. 99 GHz 200 k. Hz TDMA/ FDMA TDMA 1. 85 -1. 99 GHz Several p /4 DQPSK 16 -QAM TDMA Several 16 -QAM 25 k. Hz 12. 5 k. HZ 300 k. Hz 25 k. Hz
Standard Type JTACS Cellular PDC Cellular Major Mobile Radio Standards in Japan Year Of Multiple Frequency Introduction Access Band 1988 1993 FDMA TDMA Modulation Channel Bandwidth 860 -925 MHz FM 25 k. Hz 810 -1501 MHz P/4 DQPSK 25 k. Hz 400/800 MHz FM 25 k. Hz 843 -925 MHz FM 12. 5 k. Hz 280 MHz FSK 12. 5 k. Hz Several FSK 10 k. Hz 1895 -1907 MHz P/4 DQPSK 300 k. Hz NTT Cellular 1979 FDMA NTACS Cellular 1993 FDMA NTT Paging 1979 FDMA NEC Paging 1979 FDMA PHS Cordless 1993 TDMA
Fourier Transform pairs Function Time Waveform w(t) Spectrum W(f) Rectangular rect(t/T) T[Sa(pf. T)] Triangular ( t /T) Unit Step {+1, t> 0 u(t) = {-1, t< 0 1/2 d(f)+1/(j 2 p f) Signum {+1, t> 0 sgn(t) = {-1, t <0 1/(jpf) Constant 1 Impulse at t=t 0 Sinc Phasor Sinusoid Gaussian Exponential, One sided Exponential, Two sided Impulse Train d(t-t 0) Sa(2 p. Wt) T[Sa(pf. T)]2 d(f) e-2 j f t 0 1/2 W rect(f/2 W) ej(w 0 t+f ) ejf (f-f 0 ) cos(wct+f) 1/2 e jf d(f-f c)+1/2 e -jf d(f+f c ) e- p (t/ t 0 )^2 e-t/T , t>=0 { { 0 , t< 0 e-|t|/T k= d(t-k. T) k=- t 0 e- p (f t 0)^2 T/(1+j 2 pf. T) 2 T/(1+(2 pf. T)^2) n= f (f-nf ), where f = 1/T n=-
Fourier Transform Theorems Operation Function Linearity A 1 w 1(t)+A 2 w 2(t) Time Delay w(t-T d) Scale Change w(at) Conjugation w Duality W(t) Real Signal Frequency Translation [w(t) is real] * (t) w(t)cos(wc t +q ) Fourier Transform A 1 W 1(f)+A 2 W 2(f) W(f) e-jw. Td 1/|a| W(f/a) W * (-f) w(-f) 1/2 [e jq W(f-f c )+e –jq W(f+f c )] Complex Signal Frequency Translation w(t)ejwct W(f-f c ) Band pass Signal Re{g(t)ejwct } 1/2[G(f-f c )+G *(-f-f c )] d nw(t )/dt n (j 2 pf) n. W(f) Differentiation Integration Convolution Multiplication by t n = � t- w( l)dl w 1 (t)*w 2 (t) - w ( l ). w (t- l )d l w 1 (t)w 2 (t) tn w(t) (j 2 pf) -1 W(f)+1/2 W(0) d (f) W 1 (f)W 2 (f) W 1 (f)* W 2 (f) = W 1 (l ). W 2 (f-l)dl (-j 2 p )-1 d n. W(f)/dnf
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