... defining the following rate regions: B1 (p) = R1 , R2 Prob M1 ≥ p , B2 (p) = R1 , R2 Prob M2 ≥ p , Ba (p) = R1 , R2 Prob Ma ≥ p , (9) where M1 , M2 , and Ma are different sets of channel conditions The ... R1 , C2 (h2 ) ≥ R2 , and C12 (H) ≥ R1 + R2 By definition, H ∈ M1 , H ∈ M2 , and H ∈ Ma As a result, N ⊂ M1 This implies that Prob (M1 ) ≥ p if Prob(N ) ≥ p Therefore, C(p) ⊂ B1 (p) Similarly, ... USA, 1 968 [5] E Biglieri, J Proakis, and S Shamai, “Fading channels: information-theoretic and communications aspects,” IEEE Transactions on Information Theory, vol 44, no 6, pp 261 9– 269 2, 1998...
... Proceedings of IEEE Global Telecommu- [15] [ 16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [ 26] nications Conference (GLOBECOM ’05), vol 6, pp 351 3 351 7, St Louis, Mo, USA, November-December ... of CDMA with random spreading,” IEEE Transactions on Information Theory, vol 45, no 2, pp 62 2 64 0, 1999 [6] A J Viterbi, “Very low rate convolutional codes for maximum theoretical performance of ... sequence,” in Proceedings of IEEE Global Telecommunication Conference (GLOBECOM ’99), vol 4, pp 2 162 –2 166 , Rio de Janeiro, Brazil, December 1999 A J Weiss and B Friedlander, “Channel estimation for...
... R9,11 R45 ,62 0 .6 0.4 0.2 Cross-correlation P1: IML/FFX MOBK023-02 0.2 0.4 0 .6 −20 −15 −10 −5 Delay (chips) 10 15 20 FIGURE 2 .6: Example cross-correlation functions for Walsh codes of length 64 for ... 20 06 15:54 SPREAD SPECTRUM TECHNIQUES FOR CODE DIVISION MULTIPLE ACCESS 33 TABLE 2.1: Code length N and the number of m-sequences Np (n) n 10 N = 2n − 15 31 63 127 255 511 1023 Np (n) 2 6 18 16 ... 2 .6 The cross-correlation is plotted for various Walsh codes of length 64 We can see that only at zero delay (i.e., n = 0) we obtain Ri, j n = P2: IML MOBK023-Buehrer.cls 32 September 28, 2006...
... the SIR is −110dBm + 130dBm = 20dB and the standard deviation √ is + 36 = 6. 08dB Converting to base e , 20 ln (10) 10 = 4 .61 6. 08 ln (10) σ = 10 = 1.40 μ= (3.2) (3.3) Now we wish to find X such ... MOBK023-Buehrer.cls 74 September 28, 20 06 15:55 CODE DIVISION MULTIPLE ACCESS (CDMA) 0.02 signals signals 20 signals 0.018 0.0 16 0.014 0.012 0.01 0.008 0.0 06 0.004 0.002 0 500 1000 1500 Total interference ... perform all calculations in base 10 The probability that the SNR exceeds 6dB is Pr{SIR} ≥ 1 06/ 10 = − Q = − Q (1.15) = 0.88 μ 6 σ (3.18) Thus, the probability of exceeding the threshold is only 88%...
... Specifically, lim ηUL = (3 .66 a) ηUL = (3 .66 b) Itotal →∞ lim (Iic +Io c )→0 P2: IML MOBK023-Buehrer.cls 108 September 28, 20 06 15:55 CODE DIVISION MULTIPLE ACCESS (CDMA) Now, rearranging (3 .64 ), we can write ... 300 350 400 FIGURE 4 .6: System throughput for FHMA system with perfect side information (N = 128, perfect codes) P1: IML/FFX MOBK023-04 P2: IML MOBK023-Buehrer.cls 124 September 28, 20 06 15:55 ... separate load levels, which we will call Limit A and Limit B Limit A is typically 60 % of pole capacity for the uplink (or 60 % of the transmit power for the downlink) and is the limit at which a base...
... MOBK023-04 P2: IML MOBK023-Buehrer.cls September 28, 20 06 15:55 1 26 P1: IML/FFX MOBK023-05 P2: IML MOBK023-Buehrer.cls September 28, 20 06 15: 56 127 CHAPTER Multiuser Detection As discussed in previous ... frequency selective Rician fading channels [64 , 65 ] as well as flat and frequency selective Rayleigh fading channels (both coherent and differentially coherent) [66 –71] The most notable difference between ... PK + N N N N (5. 56) P1: IML/FFX MOBK023-05 P2: IML MOBK023-Buehrer.cls September 28, 20 06 15: 56 MULTIUSER DETECTION 145 70 Perfect cancellation assumption Linear cancellation 60 Normalized receive...
... September 1998.doi:10.1109 /35. 71 461 6 [ 26] T Kasami, “Weight distribution formula for some class of cyclic codes,” University of Illinois – Urbana, Tech Rep R-285, April 1 966 [27] L R Welch, “Lower ... IEEE, vol 68 , pp 593 61 9, May 1980 [24] R Gold, “Optimum binary sequences for spread spectrum multiplexing,” IEEE Transactions on Information Theory, vol 13, pp 61 9 62 1, October 1 967 doi:10.1109/TIT.1 967 .1054048 ... September 28, 20 06 15: 56 MULTIUSER DETECTION 169 Probability of bit error 10-1 10-2 10 -3 0-stage 1-stage 2-stage 3-stage 6- stage Single-user bound 10-4 10 20 30 40 Number of active users 50 60 FIGURE...
... tiến hệthống di động cho hệthống toàn cầu (GSM/EDGE).Nền 3GPP ngày mà công nghệ WCDMA chuẩn hóa theo việc lựa chọn công nghệ kỹ thuật từ khu vực khác năm 1997.Theo đó, WCDMA lựa chọn vài khu ... cầu (GSA) công nghệ 3,5G (HSDPA) chiếm đến 69 % tổng số mạng di động toàn cầu Nếu 20 06, có 166 mạng di động hỗ trợ HSDPA 75 nước, kết thúc năm 2007, số nhà mạng sử dụng công nghệ 204, 89 quốc gia ... khác năm 1997.Theo đó, WCDMA lựa chọn vài khu vực sở cho hệthốngthông tin di động hệ thứ 3, trở thành nguyên lý công nghệ cho hoạt động vài khu vực lân cận Do đó, đến cuối năm 1998, Mỹ, châu...
... SYNCHRONIZATION AND CHANNEL ESTIMATION EVOLUTION OF WIMAX AND LTE Nhóm CONCLUSION INTRODUCTION - IEEE 802.16e-based WiMAX and Third Generation Partnership Project (3GPP)-based Long Term Evolution (LTE) are ... The pseudorandom sequence to be sent on the subcarriers is specified in is fixed the IEEE 802.16e standard - The Zadoff-Chu sequence loaded onto the subcarriers is specified in the - A mobile ... carriers to obtain wider Forming fixed size physical resource units (PRUs) Nhóm Base on the IEEE 802.16m standard WiMAXv2 and LTE-A CONCLUSION Nhóm This article has compared the use of OFDMA in WiMAX...
... IMT-Advanced cho hệthống không dây 4G Sự phát triển WiMax WiMAXv2 dựa tiêu chuẩn IEEE 802.16m, có khả tương thích ngược với hệthống WiMAX 802.16e tiêu chí quan trọng Với đặc điểm OFDMA, 802.16m không ... so với hệthống LTE Tuy nhiên, LTE-A WiMAXv2 tương tự góc lớp vật lý; vậy, yếu tố phi công nghệ khả tương thích ngược, quy định chi phí sản phẩm có nhiều phương diện việc lựa chọn cho hệthông ... điểm thời gian-tần số kênh vào tính toán Ví dụ, MUD (multi user diversity) sử dụng hệthống 3,5G EVDO HSPA cách sử dụng tính chất thời gian khác kênh Tuy nhiên, hệthống OFDMA, có khả sử dụng...
... Algorithms 56 4.3.3 Frequency-domain Estimation 58 4.4 CRLB Analysis for LS Estimators 63 4.5 Numerical Results and Discussion 66 4.5.1 Performance of ... Fig.4 .6: Samples selection for channel estimation from FFT-demodulated OFDMA block 62 Fig.4.7: MSE performance of LS-T and LMMSE 68 Fig.4.8: Comparison between LS-T and LS-F 69 ... Fig 3.5: Noise enhancement characteristic of MMSE ICI suppression 35 Fig.3 .6: Flowchart of MMSE-SD detection 36 Fig.3.7: Average symbol error rates versus SNR with perfect CIR ...