Modulation and coding course- lecture 9

... error detection and correction codes Lecture 9 7 Why using error correction coding?  Error performance vs. bandwidth  Power vs. bandwidth  Data rate vs. bandwidth  Capacity vs. bandwidth (dB) ... jnj n tj M pp j n P − += − ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ ≤ ∑ )1( 1 jnj n tj B pp j n j n P − += − ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ ≈ ∑ )1( 1 1 p Digital Communications I: Modulation and Coding Course Period 3 -...

Ngày tải lên: 25/10/2013, 06:15

... bits Lecture 10 2 Last time, we talked about:  Channel coding  Linear block codes  The error detection and correction capability  Encoding and decoding  Hamming codes  Cyclic codes Lecture ... Digital Communications I: Modulation and Coding Course Period 3 - 2007 Catharina Logothetis Lecture 10 Lecture 10 10 Effective code rate  Initialize the memory before encoding...

Ngày tải lên: 25/10/2013, 06:15

... 2007 Catharina Logothetis Lecture 12 Lecture 12 5 Soft and hard decision decoding  In hard decision:  The demodulator makes a firm or hard decision whether one or zero is transmitted and provides no ... distance.  The coding gain is upper bounded ⎣ ⎦ 2/)1( −= f dt )(log10 gain coding 10 fc dR≤ Lecture 12 23 Performance bounds …  Basic coding gain (dB) for soft-decision...

Ngày tải lên: 29/10/2013, 13:15

... Modulation, Demodulation and Coding Course Period 3 - 2007 Catharina Logothetis Lecture 11 Lecture 11 10 Trellis – cont’d 1/11 0/00 0/10 1/11 1/01 0/00 0/11 0/10 0/01 1/11 1/01 1/00 0/00 0/11 0/10 0/01 0/00 0/11 0/00 6 t 1 t 2 t 3 t 4 t 5 t 1 ...  Decoding based on soft-bits, is called the “soft-decision decoding”.  On AWGN channels, 2 dB and on fading channels 6 dB gain are o...

Ngày tải lên: 29/10/2013, 13:15

... signal  Baseband versus bandpass:  Bandwidth dilemma:  Bandlimited signals are not realizable!  Realizable signals have infinite bandwidth! Baseband signal Bandpass signal Local oscillator Lecture ... oscillator Lecture 1 25 Bandwidth of signal …  Different definition of bandwidth: a) Half-power bandwidth b) Noise equivalent bandwidth c) Null-to-null bandwidth a) Fractional power c...

Ngày tải lên: 08/11/2013, 18:15

... I: Modulation and Coding Course Period 3 – 200/ Catharina Logothetis Lecture 2 Lecture 2 10 Encoding (PCM)  A uniform linear quantizer is called Pulse Code Modulation (PCM).  Pulse code modulation ... density, random process, linear systems and signal bandwidth. Lecture 2 20 Spectra of PCM waveforms Lecture 2 21 M-ary pulse modulation  M-ary pulse modulations categor...

Ngày tải lên: 08/11/2013, 18:15

... non-uniform  Baseband modulation  Binary pulse modulation  M-ary pulse modulation  M-PAM (M-ay Pulse amplitude modulation) Lecture 3 3 Formatting and transmission of baseband signal  Information ... statistic) Baseband pulse Received waveform Step 1 – waveform to sample transformation Step 2 – decision making )(tr )(Tz i m ˆ Demodulate & Sample Detect Lecture 3 13 Baseba...

Ngày tải lên: 27/01/2014, 08:20

... A 0 1 s 2 s T A T A− 0 0 Tt )( 1 t ψ T 1 0 0)()()()( )()()(),( /)(/)()( )( 122 0 1212 1111 0 2 2 11 =−−= −=>=< == == ∫ ∫ tAtstd Adtttstts AtsEtst AdttsE T T ψ ψψ ψ 1 2 Digital Communications I: Modulation and Coding Course Period 3 - 2007 Catharina Logothetis Lecture 4 Lecture 4 20 Implementation of matched filter receiver )(tr 1 z )( 1 tT ... filter to maximize SNR  Matched...

Ngày tải lên: 27/01/2014, 08:20

... iEE sii s s ski Ed ki Ed 2 2 min , = ≠ = Digital Communications I: Modulation and Coding Course Period 3 - 2007 Catharina Logothetis Lecture 5 Lecture 5 20 Eb/No figure of merit in digital communications  ... PAM T t )( 1 t ψ T 1 0 Lecture 5 2 Last time we talked about:  Receiver structure  Impact of AWGN and ISI on the transmitted signal  Optimum filter to maximize SNR ...

Ngày tải lên: 27/01/2014, 08:20

... capability  Interference and noise immunity  Implementation cost and complexity Digital Communications I: Modulation and Coding Course Term 3 – 2008 Catharina Logothetis Lecture 2 Lecture 2 20 Spectra ... waveforms Lecture 2 21 M-ary pulse modulation  M-ary pulse modulations category:  M-ary pulse-amplitude modulation (PAM)  M-ary pulse-position modulation (PPM) ...

Ngày tải lên: 23/03/2014, 10:21