Theory and applications of ofdm and cdma wideband wireless communications phần 10 docx

... INDEX Nyquist base, 9 criterion, 10 pulse, 9 OFDM, 1, 145 OFDM and nonlinearities, 166 symbol, 159 OFDM with convolutional coding, 208, 213 OFDM with QAM, 213 OFDM with QPSK, 208 Omni cell, 270 Open-loop ... 384, 391 Channel coding, 93, 245 Theory and Applications of OFDM and CDMA Henrik Schulze and Christian L ¨ uders  2005 John Wiley & Sons, Ltd Channel cod...

Ngày tải lên: 09/08/2014, 19:22

... (1.17) Theory and Applications of OFDM and CDMA Wideband Wireless Communications Henrik Schulze and Christian L ¨ uders Both of Fachhochschule S¨udwestfalen Meschede, Germany x PREFACE and modulation. ... examples of CDMA applications we discuss the most important systems already mentioned, namely, GPS, cdmaOne (IS-95), cdma2 000 and UMTS with its two transm...

Ngày tải lên: 09/08/2014, 19:22

... Example of a discrete (a) and continuous (b) Doppler spectrum. 42 BASICS OF DIGITAL COMMUNICATIONS Q I Figure 1.17 The 64-QAM constellation. 0 5 10 15 20 10 –6 10 –5 10 –4 10 –3 10 –2 10 –1 10 0 E b /N 0 ... fluctuations of the received time signal for ν max = 50 Hz, corresponding for example, to a transmit signal at 900 MHz for a vehicle Theory and Applications...

Ngày tải lên: 09/08/2014, 19:22

... is often convenient to work with code words of finite length, but it is not necessary, and the length is not determined by the code. Theory and Applications of OFDM and CDMA Henrik Schulze and ... L-value of the random bit S. We note that L(S = s) = sL. (3 .10) The L-value of a random bit S (written as a sign) has a very natural interpretation as a soft bit. The sign...

Ngày tải lên: 09/08/2014, 19:22

... duration that is matched to the channel and parallelize the given data stream in an appropriate way. Theory and Applications of OFDM and CDMA Henrik Schulze and Christian L ¨ uders  2005 John Wiley ... transmitter and receiver and it is not relevant for the description of the OFDM signal in the air. 2 Here we have adopted the terminology used in the specification of...

Ngày tải lên: 09/08/2014, 19:22

... efficiency of the windowing method for an OFDM signal with a high number of carriers. Figure 4.19 shows the OFDM spectra for K = 1536 and δ = 0, /16,/8,/4. We note a very steep decay for the out -of- band ... 40 –50 –40 –30 –20 10 0 10 Normalized frequency fT Power spectrum [dB] K = 48 100 0 100 –50 –40 –30 –20 10 0 10 Normalized frequency fT Power spectrum [dB] K = 192...

Ngày tải lên: 09/08/2014, 19:22

... 0.8 K = 48, L = 80 OFDM with 16- QAM and R c = 0.5 CE ideal CE real Figure 4.73 Simulation of narrowband OFDM for a slow and flat channel. 0 5 10 15 20 10 −4 10 −3 10 −2 10 −1 10 0 SNR [dB] BER n max T S = ...  Convol. encoder Bit interl. OFDM a i b i s i s(t) mapper Symbol c (k) l Figure 4.54 Transmitter block diagram for an OFDM system with convolutional coding an...

Ngày tải lên: 09/08/2014, 19:22

... values of the 1 11 10 + + 1 01 ++ 1 0 0 0, 0 0 1, , 1 1 1 8initialsettin g s + c 0 =1 1100 10 0 c 1 = 1101 111 0 c 2 =101 0101 0 c 3 =100 1000 0 c 4 =011 1100 0 c 5 = 0100 001 0 c 6 =00 1101 1 0 c 7 =0000 110 ... multiplication of the data symbols by a spreading sequence of pseudoran- dom signs. These sequences are called pseudonoise (PN) sequences or code signals. We Theory and...

Ngày tải lên: 09/08/2014, 19:22

... number of base stations involved in a soft handover should be kept small. To illustrate this soft handover effort, Figure 5.23 shows the fraction of connections involved in a soft (or softer) handover ... interval. For MC -CDMA (multicarrier CDMA) with OFDM and guard interval, we may write g  k (t) = N  i=1 γ ik ψ  i (t) (5 .10) instead of Equation (5.9). However, to keep the...

Ngày tải lên: 09/08/2014, 19:22

... using pure CDMA and a time division duplex (TDD) mode using a combination of CDMA and TDMA as the multiple access scheme. The FDD mode is based on a proposal originally called the Wideband CDMA (WCDMA), ... While the WCDMA and TD -CDMA- based modes use a chip rate of 3.84 Mchip/s and a carrier separation of about 5 MHz, the chip rate for the TD-SCDMA mode is 1.28 Mchip/s...

Ngày tải lên: 09/08/2014, 19:22