... 0,038 0, 060 0,091 0,193 0,208 0,323 0,503 0,710 0, 862 0,954 0,995 0,995 Bc súng (nm) 570 585 595 60 0 61 0 62 1 63 0 64 0 65 0 66 0 67 0 68 0 69 0 700 710 720 23 trng tng i 0,952 0,870 0,757 0 ,63 1 0,503 ... 555nm v 61 0nm, s cú sỏng 0,5 hot ng 61 0nm so vi sỏng hot ng 555 nm BNG TRNG TNG I ( = Ti bc súng 555 nm) Bc súng (nm) 410 420 430 443 450 460 470 480 490 500 510 520 530 540 550 560 trng ... loi kim chõn khụng b, b chiu sỏng s phỏt cỏc electron; nng lng ca cỏc electron ú khụng ph thuc vo cng ca ỏnh sỏng chiu vo m ph thuc vo tn s ỏnh sỏng Anhstanh cho rng c chiu ti b mt kim loi, mi...
... transmit at 0. 76 nat per second while achieve an outage probability smaller than 10% With 16 antenna elements at the base station, both mobiles can transmit at 2.25 nat per second while achieving an ... 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 ... mobile is allowed to transmit, then it can achieve capacity C(h1 ) Similarly, if only mobile is allowed to transmit, it can achieve capacity C(h2 ) An achievable time-share capacity region is given...
... log-likelihood ratios per chip are calculated (one for each received sample influenced by this chip) and summed up to obtain the LLR of the chip The LLR of the chip in layer m of user u at chip index k in ... on soft chip values from the decoder All layers from all active users are simultaneously taken into account In case of perfect channel knowledge and soft chips matching the transmitted chips, ... soft chips.1 Since the subsequent processing is based on the reinterleaved soft chips, we concentrate on the latter, and denote the reinterleaved soft chip of (i) user u and layer m at chip index...
... 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...
... September 28, 20 06 15:54 CODE DIVISION MULTIPLE ACCESS (CDMA) 10 K=1 K = 10 K = 20 K = 30 K = 40 -1 10 -2 10 Probability of bit error 62 -3 10 -4 10 -5 10 -6 10 10 Eb/No (dB) 12 14 16 18 20 FIGURE ... MOBK023-Buehrer.cls 56 September 28, 20 06 15:54 CODE DIVISION MULTIPLE ACCESS (CDMA) 0.9 0.8 B B B B B B = = = = = = CW tone 25 MHz 100 MHz 225 MHz 400 MHz 500 MHz 0.7 0 .6 CDF P1: IML/FFX MOBK023-02 ... cos(ωc t + φk )] d t = Additionally, the variance of n is σn = (2 .66 ) j =1, j =k (i+1)T+τk i T+τk E[n(t)a k (t − τk ) N0 Tb (2 .67 ) K provided that ωc 2/Tb We now require the statistics of j =1,...
... 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 ... 20 06 15:55 CODE DIVISION MULTIPLE ACCESS (CDMA) Solution: The two signals are transmitted at the same time, and thus the second signal arrives 60 0m/(3 ∗ 108 m/s) = μs This corresponds to two chips ... 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...
... 1995.doi:10.1049/el:19 9414 33 [112] R M Buehrer and S P Nicoloso, “Comments on partial interference cancellation,” IEEE Transactions on Communications, vol 47, pp 65 8 66 1, May 1999 doi:10.1109/ 26. 768 754 [113] ... 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 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 bounds...
... số liệu Nghiệp đoàn di động toàn cầu (GSA) công nghệ 3,5G (HSDPA) chi m 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 ... việc Vấn đề nghiên cứu kết thúc vào tháng năm 2004, với việc bắt đầu 3GPP với lớp vật lý HARQ kỹ thuật dựa vào node B đường lên độ dài TTI đường lên ngắn Do đó ,chi tiết hình thành nhanh DCH đưa ... riêng’ vào tháng 12 năm 2002 Từ bên cung ứng Motorola, Nokia, Ericsson công ty trụ cột để bắt đầu nghiên cứu GPP Sự đầu tư công nghệ việc nghiên cứu HSUPA hình sau Sau nghiên cứu chitiết giới...
... 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...
... OFDM gom với để giảm thiểu chi phí tín hiệu đạt độ chitiết tỷ lệ đạt để hỗ trợ dịch vụ khác Trong WiMAX, kênh hình thành từ nhóm sóng mang ký tự OFDM Có hai phương pháp chia nhỏ kênh quan trọng, ... đặc tính kênh thừa hưởng mạnh mẽ LTE với chi phí thông tin phản hồi chitiết WiMAX có xu hướng sử dụng phân tập tần số nhiều tình không phụ thuộc mức vào phản hồi Trong môi trường tốc độ cao, ... gian cố định mức 10 ms,không phân biệt băng thông hoạt động, trình tự gửi trung tâm có 64 sóng mang chi m 0. 96 MHz băng thông.Do đó,không giống phần đầu WiMAX,số lượng sóng mang sử dụng PSS cố định...
... 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 ... suppression scheme that maximizes overall 31 achievable rate is derived and proven as an equivalent of the MMSE solution As described in [44] [60 ], the overall achievable rate can be maximized if the...