orthogonal frequency division multiple access

... result, capacities for single-cell CDMA systems can be substantially lower than those fororthogonal multiple access techniques such as TDMA or FDMA In addition, if one of thereceived signals is significantly ... Detection As discussed in previous chapters, the conventional matched filter receiver treats multiple accessinterference (MAI), which is inherent in CDMA, as if it were additive noise because, ... K ^ ^ ^ FIGURE 5.3: Block diagram of generic linear sub-optimal receiver structures If the multiple access channel (excluding noise) is viewed as a deterministic multi-input multi-output linear

Ngày tải lên: 07/08/2014, 21:20

... CODE DIVISION MULTIPLE ACCESS (CDMA) [14] F A Tobagi and L Kleinrock, “Packet switching in radio channels: Part III—Polling and (dynamic) split-channel reservation multiple access, ... C Wu and V O K Li, “Receiver-initiated busy-tone multiple access in packet radio networks,”... synchronous code- division multiple- access channel,” IEEE Transactions on Communications, ... Data Communications, pp 39–49, 1997 [17] Z J Haas and J Deng, “Dual busy tone multiple access (DBTMA)—a multiple access control scheme for ad hoc networks,” IEEE Transactions on Communications,

Ngày tải lên: 07/08/2014, 21:20

... Trang 1 CHƯƠNG 1: GIỚI THIỆU1.1 Giơí thiệu chung Kỹ thuật OFDM ( Orthogonal frequency-division multiplexing) là một trường hợp đặc biệt của phương pháp điều chế đa sóng mang, trong ... niệm OFDM Kỹ thuật OFDM là kỹ thuật ghép kênh phân chia theo tần số trực giao(Orthogonal Frequency Division Multiplexing) Đó là sự kết hợp giữa mã hóa vàghép kênh Thường thường nói tới ghép ... sau đó ghép kênh lại để tao nên sóng mang OFDM OFDM là trường hợp đặc biệt của FDM (Frequency Divison Multiplex), trong kỹ thuật FDM băng tần tổng của đường truyền được chia thành N kênh tần

Ngày tải lên: 16/10/2014, 21:48

... tải hiệu quả hơn 2.2 Sự khác nhau giữa OFDM và FDM (Frequency Division Multiplexing) Kỹ thuật ghép kênh theo tần số FDM (Frequency Division Multiplexing) làtruyền đồng thời các tín hiệu nhánh ... trong các ứng dụng thực tế Một số biến thể phổ biến bao gồm:  OFDMA: OFDMA (Orthogonal Frequency Division Multiple Access) là một biếnthể của OFDM cho phép nhiều người dùng sử dụng cùng một băng ... Viễn thông **************** Báo cáo đồ án: Chuyên đề viễn thông Kỹ thuật OFDM (Orthogonal frequency division multiplexing) Hướng dẫn : T.S Võ Duy Phúc Thực hiện: Nguyễn Thị Thu Thảo (106200037)

Ngày tải lên: 20/08/2024, 15:07

... full text (HTML) versions will be made available soon. Decentralized estimation over orthogonal multiple- access fading channels in wireless sensor networks optimal and suboptimal estimators ... in Signal Trang 2Decentralized estimation over orthogonal access fading channels in wireless sensor networks— optimal and suboptimal estimatorsmultiple-Xin Wang∗1 and Chenyang Yang1 1 School ... suboptimal decentralized estimators in wireless sensor networks over orthogonal access fading channels in this paper Considering multiple-bit quantization for digital transmission, we developmaximum

Ngày tải lên: 18/06/2014, 22:20

... full text (HTML) versions will be made available soon. Decentralized estimation over orthogonal multiple- access fading channels in wireless sensor networks optimal and suboptimal estimators ... in Signal Trang 2Decentralized estimation over orthogonal access fading channels in wireless sensor networks— optimal and suboptimal estimatorsmultiple-Xin Wang∗1 and Chenyang Yang1 1 School ... suboptimal decentralized estimators in wireless sensor networks over orthogonal access fading channels in this paper Considering multiple-bit quantization for digital transmission, we developmaximum

Ngày tải lên: 20/06/2014, 04:20

... transmit their messages on orthogonal channels, as this enables “per-user” decoding rather than joint decoding In this paper, we will consider the design of orthogonal multiple access systems with a ... Recommended by J Wang We study the problem of joint power and channel resource allocation for orthogonal multiple access relay (MAR) systems in order to maximize the achievable rate region Four relaying ... 476125, 15 pages doi:10.1155/2008/476125 Research Article Power and Resource Allocation for Orthogonal Multiple Access Relay Systems Wessam Mesbah and Timothy N Davidson Department of Electrical and

Ngày tải lên: 22/06/2014, 01:20

... MC-MFSK systems transmit on multiple frequency carriers simultaneously The system allows multiple-user access with its users sharing the same frequency and time space These multiple users are differentiated ... PERFORMANCE OF MULTIPLE ACCESS MULTI-CARRIER MULTILEVEL FREQUENCY SHIFT KEYING SYSTEMS TAY HAN SIONG NATIONAL UNIVERSITY OF SINGAPORE 2005 Trang 2OPTIMIZING PERFORMANCE OF MULTIPLE ACCESS MULTI-CARRIER ... Multi-carrier Multilevel Frequency Shift Keying (MC-MFSK) system is a form of multi-tone MFSK systems, and it transmits on multiple frequency carriers simultaneously The number of frequency-carriers

Ngày tải lên: 27/11/2015, 12:32

... TIN SỐ Đề tài: Kỹ thuật đa truy cập phi trực giao NOMA trong mạng 5G A survey of Non-Orthogonal Multiple Access for 5G Học viên thực hiện : PHẠM QUỐC CƯỜNG Giảng viên hướng dẫn: PGS TS BÙI THỊ ... thuật đa truy cập định nghĩa bởi phần mềm SoDeMA Nghiên cứu kỹ thuật SoDeMA (Software Defined Multiple Access) để có thể tận dụng ưu điểm của kỹ thuật OMA và NOMA trong từng điều kiện cụ thể bởi ... lượng userlớn hơn số lượng khe tài nguyên trực giao nhờ việc cấp phát tài nguyên phi trực giao (non-orthogonal) Kỹ thuật NOMA về cơ bản chia thành 2 loại: Kỹ thuật NOMA miền công suất (Power-domain

Ngày tải lên: 20/03/2022, 14:37

... MA schemes including orthogonal multiple access (OMA) and non-orthogonal multiple access (NOMA), these considered main categories are deployed to primarily pro-vide multiple access methodology ... non-existence of the direct link between source and destination This paper employs non-orthogonal multiple access (NOMA) scheme to serve large num-ber of users at different allocated power levels ... corroborate the proposed methodology Keywords Strictly positive secrecy capacity · Non-orthogonal multiple access · Jamming signal · Secure outage probability · Physical layer security * Dinh-Thuan

Ngày tải lên: 22/11/2022, 14:09

... TIN SỐ Đề tài: Kỹ thuật đa truy cập phi trực giao NOMA trong mạng 5G A survey of Non-Orthogonal Multiple Access for 5G Học viên thực hiện : PHẠM QUỐC CƯỜNG Giảng viên hướng dẫn: PGS TS BÙI THỊ ... thuật đa truy cập định nghĩa bởi phần mềm SoDeMA Nghiên cứu kỹ thuật SoDeMA (Software Defined Multiple Access) để có thể tận dụng ưu điểm của kỹ thuật OMA và NOMA trong từng điều kiện cụ thể bởi ... lượng userlớn hơn số lượng khe tài nguyên trực giao nhờ việc cấp phát tài nguyên phi trực giao (non-orthogonal) Kỹ thuật NOMA về cơ bản chia thành 2 loại: Kỹ thuật NOMA miền công suất (Power-domain

Ngày tải lên: 11/12/2022, 04:31

... several common technologies with subtle differences.The main common technology is orthogonal frequency- division multiple access (OFDMA) - There are many good reasons for choosing OFDMA such as multipath ... bandwidths, the ability to handle different data rates, and the ability to easily combine with multiple antenna techniques Nhóm - The focus of this article is on the comparative use of OFDMA ... WIMAX AND LTE RESOURCE MAPPING FROM SUBCARRIERS Subcarriers are the smallest granular units in the frequency domain, OFDM symbol duration is the smallest granular unit in the time domain in OFDMA...

Ngày tải lên: 24/07/2015, 22:26

... Typical OFDM-based multiple access techniques include Time Division Multiple Access (OFDM-TDMA), Code Division Multiple Access (OFDM-CDMA or MC-CDMA) and Frequency Division Multiple Access (OFDM-FDMA) ... division multiple access MSE mean square error CFO carrier frequency offset OFDM orthogonal frequency division multiplexing CP cyclic prefix OFDMA orthogonal frequency division multiple access CRLB ... communications, Orthogonal Frequency Division Multiplex (OFDM) is widely accepted as a major technique for many future broadband wireless systems OFDMA, a multiuser OFDM using Frequency Division Multiple Access...

Ngày tải lên: 14/09/2015, 14:03

... keying (QPSK) Sophisticated multiple access technology like frequency division multiple access (FDMA), time division multiple access (TDMA) and code division multiple access (CDMA) also gained ... systems, multiple access technologies based on orthogonal frequency division multiplexing (OFDM) air interface were chosen [8] In the downlink, the popular orthogonal frequency division multiple access ... Code Division Multiple Access DFT Discrete Fourier Transform FDE Frequency Domain Equalizer FDMA Frequency Division Multiple Access FEC Forward Error Correcting FFT Fast Fourier Transform FH Frequency...

Ngày tải lên: 08/09/2015, 18:24

... power loading Multiple access The resources available in a CR system must be shared among the radios OFDM supports several multiple access techniques In Frequency Division Multiple Access (FDMA), ... and TDMA, a combinatorial multiple access scheme was invented for OFDM systems known as orthogonal frequency division multiple access (OFDMA) OFDMA partitions both frequency and time dimensions, ... access control MBLP Mixed binary linear programming ACRONYMS xiv MINLP Mixed integer nonlinear programming MS Mobile station OFDM Orthogonal frequency division multiplexing OFDMA Orthogonal frequency...

Ngày tải lên: 09/09/2015, 10:19

... European Telecommunication Standard Institute fc frequency carrier FDM Frequency Division Multiplexing FDMA Frequency Division Multiple Access Fd Doppler Frequency FEC Forward Error Correction FFT ... Phase Shift Keying BS Base Station BWA Broadband Wireless Access CDMA Code Division Multiple Access COFDM Coded Orthogonal Frequency Division Multiplexing CPE Customer-premises equipment d2(y,z) squared ... Cellular (PDC), Code Division Multiple Access (CDMA-2000), Wideband Code Division Multiple Access/ Universal Mobile Telecommunications System (WCDMA/UMTS), High Speed Downlink Packet Access (HSDPA),...

Ngày tải lên: 26/05/2013, 21:28

... 2002 [4] L J Cimini Jr., “Analysis and simulation of a digital mobile channel using orthogonal frequency division multiplexing,” IEEE Transactions on Communications, vol 33, no 7, pp 665– 675, 1985 ... IEEE P802.15-03/268r2, November 2003 [6] B L Floch, M Alard, and C Berrou, “Coded orthogonal frequency division multiplex,” Proceedings of the IEEE, vol 83, no 6, pp 982–996, 1995 [7] G Ungerboeck, ... parameters of the model, and p is the order of the model Based on the frequency- domain measurements in the 4.3 GHz to 5.6 GHz frequency band, a second-order (p = 2) AR model is reported to be sufficient...

Ngày tải lên: 22/06/2014, 22:20

... cases with multiple users, that is, there is virtually no loss in power efficiency compared to the case without MAI We therefore obtain a quasiorthogonal multiple access without the need for orthogonal ... spread-spectrum multiple- access channels,” IEEE Journal on Selected Areas in Communications, vol 8, no 4, pp 641–649, 1990 [7] P A Hoeher and H Schoeneich, “Interleave -division multiple access from ... downlink multiple access capacity for Beyond 3G,” IEEE Communications Magazine, vol 43, no 1, pp 61–69, 2005 [10] J C Fricke, H Schoeneich, and P A Hoeher, “An interleavedivision multiple access...

Ngày tải lên: 22/06/2014, 23:20

... of multiple- access system with multiple antennas at the base station Most previous studies are constrained to either fixed channel condition [11, 12] or ergodic capacity region [13] The space -division ... maximize the sum capacity of a time invariant Gaussian MIMO multiple- access channel The ergodic capacity region for MIMO multiple- access channel with covariance feedback has been studied in [13] ... with multiple antennas,” IEEE Transactions on Information Theory, vol 47, no 4, pp 1273–1289, 2001 [11] B Suard, G Xu, H Liu, and T Kailath, “Uplink channel capacity of space -division- multiple- access...

Ngày tải lên: 23/06/2014, 01:20

... understood orthogonal access techniques such as time division multiple access and frequency division multiple access Additionally, random access schemes such as carrier sense multiple access are ... Techniques for Code Division Multiple Access 23 2.1 Forms of Code Division Multiple Access 23 2.2 Direct Sequence Code Division Multiple Access ... contention-free multiple access is in how the channels are defined In time division multiple access (TDMA), channels are defined according to time slots In frequency division multiple access (FDMA),...

Ngày tải lên: 27/06/2014, 14:20