adaptive modulation and coding

... (1) where Ri corresponds to the data rate of the ith adaptive modulation and coding scheme (i ∈ I, where I is the set of all adaptive schemes) and Pi(c,m) ∈ {0, 1} is a frame error indicator (It ... coding At a fixed modulation and coding scheme, the Alamouti coded system therefore has an increasing SNR advantage for large SNR values However, since we are considering a coded system with adaptive ... with adaptive modulation and coding, the operating points on the uncoded BER curves are between BER= 10−1 and BER= 10−2 At these large BER values, the SNR gain due to Alamouti coding is only...

Ngày tải lên: 22/06/2014, 06:20

... adaptive multiresolution modulation and coding scheme which combines a multilayer video encoding and delivery scheme with an adaptive nonuniform phase-shift keyed (PSK) modulation/ coding strategy The ... memory M = 10 and a corresponding puncturing period P = ADAPTIVE MULTIRESOLUTION MODULATION AND CODING SCHEME A block diagram of the proposed adaptive multiresolution modulation/ coding (AMC) system ... source coding compared to single-layer source coding In particular, this performance gap is why we provide a switch in the adaptive modulation/ coding scheme to revert to a single-layer source coding...

Ngày tải lên: 22/06/2014, 19:20

... Nyquist bandwidth constraint Nyquist bandwidth constraint: The theoretical minimum required system bandwidth to detect Rs [symbols/s] without ISI is Rs/2 [Hz] Equivalently, a system with bandwidth ... ≥ [symbol/s/Hz] 2T W Bandwidth efficiency, R/W [bits/s/Hz] : An important measure in DCs representing data throughput per hertz of bandwidth Showing how efficiently the bandwidth resources are ... noise and no ISI) Lecture 16 Example of eye pattern: Binary-PAM, SRRQ pulse … AWGN (Eb/N0=20 dB) and no ISI Lecture 17 Example of eye pattern: Binary-PAM, SRRQ pulse … AWGN (Eb/N0=10 dB) and no...

Ngày tải lên: 18/10/2013, 06:15

... Last time, we talked about: Channel coding Linear block codes The error detection and correction capability Encoding and decoding Hamming codes Cyclic codes Lecture 10 Today, ... k , K ) or (k / n, K ) where Rc = k / n is the coding rate, determining the number of data bits per coded bit In practice, usually k=1 is chosen and we assume that from now on K is the constraint ... (11 10 00 10 11) Effective code rate Initialize the memory before encoding the first bit (allzero) Clear out the memory after encoding the last bit (allzero) Hence, a tail of zero-bits is appended...

Ngày tải lên: 25/10/2013, 06:15

... detection and correction codes Lecture Why using error correction coding? Error performance vs bandwidth Power vs bandwidth P Data rate vs bandwidth Capacity vs bandwidth B Coded A F Coding gain: ... error detection and correction capability Encoding and decoding Hamming codes Cyclic codes Lecture Block diagram of a DCS Format Source encode Channel encode Pulse modulate Bandpass modulate ... Bandpass modulate Channel Digital modulation Digital demodulation Format Source decode Channel decode Lecture Detect Demod Sample What is channel coding? Channel coding: Transforming signals to...

Ngày tải lên: 25/10/2013, 06:15

... Lecture 12 Soft and hard decision decoding … ML soft-decisions decoding rule: Choose the path in the trellis with minimum Euclidean distance from the received sequence ML hard-decisions decoding rule: ... length, decreasing the coding rate, usually increases the free distance The coding gain is upper bounded coding gain ≤ 10 log10 ( Rc d f ) Lecture 12 22 Performance bounds … Basic coding gain (dB) ... code uses two levels on coding, an inner code and an outer code (higher rate) Popular concatenated codes: Convolutional codes with Viterbi decoding as the inner code and Reed-Solomon codes as...

Ngày tải lên: 29/10/2013, 13:15

... two levels Decoding based on soft-bits, is called the “soft-decision decoding” On AWGN channels, dB and on fading channels dB gain are obtained by using soft-decoding over hard-decoding Lecture ... possible codewords: sequence and L codewords to search!!! ML decoding rule: Choose U ( m′) if p(Z | U ( m′) ) = max(m) p(Z | U ( m ) ) over all U Lecture 11 11 ML decoding for memory-less channels ... quantized only to two level) which are called “hardbits” Decoding based on hard-bits is called the “hard-decision decoding” Lecture 11 15 Soft and hard decision-cont’d In Soft decision: The demodulator...

Ngày tải lên: 29/10/2013, 13:15

... digital communication system (DCS): Utilized techniques Formatting and source coding Modulation (Baseband and bandpass signaling) Channel coding Equalization Synchronization Design goals Trade-offs ... Low-pass Band-pass High-pass Realizable filters: RC filters Butterworth filter Lecture 23 Bandwidth of signal Baseband versus bandpass: Baseband signal Bandpass signal Local oscillator Bandwidth ... Bandwidth dilemma: Bandlimited signals are not realizable! Realizable signals have infinite bandwidth! Lecture 24 Bandwidth of signal … Different definition of bandwidth: a) Half-power bandwidth b) Noise...

Ngày tải lên: 08/11/2013, 18:15

... Implementation cost and complexity Lecture 19 Spectra of PCM waveforms Lecture 20 M-ary pulse modulation M-ary pulse modulations category: M-ary pulse-amplitude modulation (PAM) M-ary pulse-position modulation ... average quantization noise power Lecture Encoding (PCM) A uniform linear quantizer is called Pulse Code Modulation (PCM) Pulse code modulation (PCM): Encoding the quantized signals into a digital ... comparing and selecting PCM waveforms: Spectral characteristics (power spectral density and bandwidth efficiency) Bit synchronization capability Error detection capability Interference and noise...

Ngày tải lên: 08/11/2013, 18:15

... Quantization Uniform and non-uniform Baseband modulation Binary pulse modulation M-ary pulse modulation M-PAM (M-ay Pulse amplitude modulation) Lecture Formatting and transmission of baseband signal Digital ... statistic) 12 ˆ mi Baseband and bandpass Bandpass model of detection process is equivalent to baseband model because: The received bandpass waveform is first transformed to a baseband waveform Equivalence ... Receiver structure Demodulation (and sampling) Detection First step for designing the receiver Matched filter receiver Correlator receiver Lecture Demodulation and detection g i (t ) Bandpass si (t...

Ngày tải lên: 27/01/2014, 08:20

... of AWGN and ISI on the transmitted signal Optimum filter to maximize SNR Matched filter receiver and Correlator receiver Lecture Receiver job Demodulation and sampling: Waveform recovery and preparing ... For bandpass signals Received waveform Receiving filter Equalizing filter ˆ mi Threshold comparison Compensation for channel induced ISI Baseband pulse (possibly distored) Lecture Baseband pulse ... we need a signal space? It is a means to convert signals to vectors and vice versa It is a means to calculate signals energy and Euclidean distances between signals Why are we interested in Euclidean...

Ngày tải lên: 27/01/2014, 08:20

... time we talked about: Receiver structure Impact of AWGN and ISI on the transmitted signal Optimum filter to maximize SNR Matched filter and correlator receiver Signal space used for detection ... deterministic Elements of noise vector n = (n1 , n2 , , nN ) are i.i.d Gaussian random variables with zero-mean and variance N / The noise vector pdf is ⎛ n2⎞ ⎟ pn (n) = exp⎜ − (πN )N / ⎜ N ⎟ ... Signal space used for detection Orthogonal N-dimensional space Signal to waveform transformation and vice versa Lecture Today we are going to talk about: Signal detection in AWGN channels Minimum...

Ngày tải lên: 27/01/2014, 08:20

... communication systems Some basic concepts and definitions such as as signal classification, spectral density, random process, linear systems and signal bandwidth Lecture 2 Today, we are going to ... average quantization noise power Lecture Encoding (PCM)   A uniform linear quantizer is called Pulse Code Modulation (PCM) Pulse code modulation (PCM): Encoding the quantized signals into a digital ... comparing and selecting PCM waveforms:      Spectral characteristics (power spectral density and bandwidth efficiency) Bit synchronization capability Error detection capability Interference and...

Ngày tải lên: 23/03/2014, 10:21

... we talked about:  Receiver structure  Impact of AWGN and ISI on the transmitted signal  Optimum filter to maximize SNR  Matched filter and correlator receiver  Signal space used for detection ... deterministic  Elements of noise vector n = (n1 , n2 , , nN ) are i.i.d Gaussian random variables with zero-mean and variance N / The noise vector pdf is  n2  pn (n) = exp − ( πN ) N /  N ... Signal space used for detection  Orthogonal N-dimensional space  Signal to waveform transformation and vice versa Lecture Today we are going to talk about:  Signal detection in AWGN channels  Minimum...

Ngày tải lên: 23/03/2014, 10:21

... Last time, we talked about:  Channel coding  Linear block codes  The error detection and correction capability  Encoding and decoding  Hamming codes  Cyclic codes Lecture 10 ... or where (k / n, K ) (n, k , K )   is the coding rate, determining the number of data bits per coded bit  RcIn=practice, usually k=1 is chosen and we assume that k/n from now on K is the constraint ... Lecture 10 Effective code rate   Initialize the memory before encoding the first bit (allzero) Clear out the memory after encoding the last bit (allzero)  Hence, a tail of zero-bits is appended...

Ngày tải lên: 30/03/2014, 10:20

... Bandwidth efficient modulation schemes  Offset QPSK (OQPSK) and Minimum shift keying   M-QAM   Bandwidth efficient and constant envelope modulations, suitable for non-linear amplifier Bandwidth ... formatting, coding, modulation  Design goals:   Probability of error and delay constraints Trade-off between parameters:   Bandwidth and power limited systems Trading power with bandwidth and vise ... cont’d Channel coding  Linear block codes (cyclic codes and Hamming codes)  Encoding and decoding structure   Generator and parity-check matrices (or polynomials), syndrome, standard array...

Ngày tải lên: 30/03/2014, 10:20

... interesting future study Abbreviations AMC: adaptive modulation and coding; BS: base station; LT: lower bound of total utility; MCS: modulation and coding scheme; MSS: mobile subscriber station; ... and IEEE Microwave Theory and Techniques Society, IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems IEEE Standard ... and IEEE Microwave Theory and Techniques Society, IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems IEEE standard...

Ngày tải lên: 21/06/2014, 02:20

... Multiplexing and Channel Coding 1.3.3.4 Spreading and Modulation 1.3.3.4.1 Downlink Spreading and Modulation 1.3.3.4.2 Uplink Spreading and Modulation 1.3.3.5 Random ... Burst-by-Burst Adaptive Wireless Transceivers 3.1 Motivation 3.2 Narrowband Burst-by-Burst Adaptive Modulation 3.3 Wideband Burst-by-Burst Adaptive Modulation ... variable rates and a range QoS are highlighted The UL and DL modulation and spreading schemes are described and UTRA and IMT 2000 are compared in terms of the various solutions standardized The...

Ngày tải lên: 20/04/2014, 09:52