Unipolar v s Bipolar Bipolair 1 puls 0
Unipolar v. s. Bipolar • Bipolair “ 1” => +puls, “ 0”=> -puls • Unipolair=> “ 1” => +puls, “ 0” => no puls Bipolar 1 0 1 1 1 0 Unipolar 31
Bipolair data signal: RZ, Manchester, NRZ 32
UNIpolar data signal: RZ, Manchester, NRZ 1 0 1 1 1 0 33
Unipolar와 bipolar 와의 관계 unipola bipola repeated 34
Manchester Biphase "1" "0" T = 0. 1 microsecond 35
NRZ random data signal spectrum, C=2. 048 MBps. O Hz. peak linear scale 2. 048 MHz 38
RZ signal 50% duty, Bipolar , 2. 048 MBps O Hz. peak Clock 2. 048 MHz Null: 2 x 2. 048 Mhz 40
Alternating Markinversion (AMI) 50% duty cycle 41
AMI 스펙트럼 50% duty cycle, 2. 048 MBps 43
AMI => HDB 3 44
Machester code의 스펙트럼 20 MHz. 0. 001 7 0 10 0 1 10 W( f 0. 0005 ) 0 3 10 7 2 10 7 1 10 7 7 2 10 7 3 10 70 f 0. 001 W( f ) 9 0. 01. 10 1 10 7 0 10 0 1 10 4 5 3 10 7 2 10 7 1 10 7 f 7 2 10 7 7 3 1046
Raised Cosine Filter 49
델타 PCM(DPCM) 64
DPCM 부호기 65
오류확률(Error Probability) • 확률 이론에 의한 시스템 성능 분석 AWGN at t=T Transmitted waveform Received waveform Down Conversion Receiving Filter Equalizing Filter Threshold Comparison 75
PDF of AWGN 76
Conditional PDF 77
Bit Error Probability(1) 78
Bit Error Probability(2) 79
Bit Error Probability(3) Ed is energy difference N 0/2 is noise spectral density is vector angle Antipodal : Orthogonal : /2 , Where, Average bit energy Correlation coefficient 80
BER 1) Coherent BPSK 2) Coherent ASK 3) Coherent BFSK 4) Non-coherent DPSK 5) Non-coherent FSK 81
- Slides: 81