orthogonal frequency division multiple

... European Telecommunication Standard Institute fc frequency carrier FDM Frequency Division Multiplexing FDMA Frequency Division Multiple Access Fd Doppler Frequency FEC Forward Error Correction FFT ... 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 Euclidean ... Square Error Mean Square Error MUX Multiplex n additive white Gaussian noise NLOS Non Line Of Sight Nw number of vanishing moments OFDM Orthogonal Frequency Division Multiplexing PDC Personal Digital...

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

... Signal processing made digitally in the frequency domain – IFFT/FFT –pair • Guard time is added to reduce effects caused by multipath propagation • Tolerant to frequency- selective fading – Information ... to frequency and phase offset errors – Peak to average power - problem Kari Pietikäinen Communications Laboratory / HUT S-72.333 Postgraduate Course in Radio Communications Subchannels • Frequency- selective ... IFFT / FFT pair is the key factor in OFDM – IFFT: From frequency domain to time domain – FFT: Vice versa • All signal processing is made in frequency domain • IFFT / FFT low implementation cost...

Ngày tải lên: 11/07/2014, 20:21

... Khái niệm OFDM Kỹ thuật OFDM kỹ thuật ghép kênh phân chia theo tần số trực giao (Orthogonal Frequency Division Multiplexing) Đó kết hợp mã hóa ghép kênh Thường thường nói tới ghép kênh người ta ... lập, mã hóa sau ghép kênh lại để tao nên sóng mang OFDM OFDM trường hợp đặc biệt FDM (Frequency Divison Multiplex), kỹ thuật FDM băng tần tổng đường truyền chia thành N kênh tần số không chồng ... đồng ký tự (symbol synchronization), đồng tần số sóng mang (carrier frequency synchronization), đồng tần số lấy mẫu (sampling frequency synchronization) 2.11.1 Đồng kí tự Đồng ký tự nhằm xác định...

Ngày tải lên: 16/10/2014, 21:48

... 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 ... 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

Ngày tải lên: 24/07/2015, 22:27

... Mixed integer nonlinear programming MS Mobile station OFDM Orthogonal frequency division multiplexing OFDMA Orthogonal frequency division multiple access OSA Opportunistic spectrum access PN Primary ... 1.3 Orthogonal frequency division multiplexingbased CR A CR requires a flexible and adaptive physical layer in order to efficiently perform its required tasks Orthogonal frequency division multiplexing ... 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,...

Ngày tải lên: 09/09/2015, 10:19

... access MSE mean square error CFO carrier frequency offset OFDM orthogonal frequency division multiplexing CP cyclic prefix OFDMA orthogonal frequency division multiple access CRLB Cramer-Rao Lower ... 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) ... 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...

Ngày tải lên: 14/09/2015, 14:03

... Minimum Carrier Spacing Frequency Digital televsion techniques – Lecture 2013 17 17 COFDM Orthogonal carriers Digital televsion techniques – Lecture 2013 18 18 COFDM Orthogonal carriers Digital ... MHz • Developed for MHz channels – A MHz variant has been produced and tested • Can use single frequency networks - SFNs • New technology with scope for continued improvement & development Digital ... amplitude Digital televsion techniques – Lecture 2013 12 12 …Mathematical description of COFDM Zeroth frequency = gives Compare with IFT Equivalent if Digital televsion techniques – Lecture 2013 13...

Ngày tải lên: 09/07/2014, 08:16

... 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 ... shift 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 ... Likelihood Sequence Estimation OCI Out-of-Cell Interference OFDM Orthogonal Frequency Division Multiplexing OFDMA Orthogonal Frequency Division Multiple Access PAPR Peak-to-Average Power Ratio PDF Probability...

Ngày tải lên: 08/09/2015, 18:24

... cost-effective way to more with your existing fiber network? The CWDM Advantage ADC Coarse Wave Division Multiplexing (CWDM) Solutions, part of the ADC’s Value-Added Module (VAM) family, add flexibility ... segregates the light to ensure only the desired combination of wavelengths are used, and 2) multiplexes and demultiplexes the signal across a single fiber link In many applications, a 1310 nm fiber ... ll Upli ite nk Hub HEA DEN D Opt ic Nod al e HIG H-RI S BUS E MDU INES / S Coarse Wavelength Division Multiplexing (CWDM) New networks require new ways of thinking A Tradition of Innovation CWDM’s...

Ngày tải lên: 21/12/2013, 07:17

... OmniReach™ FTTX Solutions Wavelength Division Multiplexer Modules Application Packet Optical Line Terminal Video Optical Line Terminal Central ... Video WDM www.adc.com • +1-952-938-8080 • 1-800-366-3891 OmniReach™ FTTX Solutions Wavelength Division Multiplexer Modules Package Style Options and WDM Schematics 9/07 • MicroVAM Style 9" LGX Style ... x73475 www.adc.com • +1-952-938-8080 • 1-800-366-3891 OmniReach™ FTTX Solutions Wavelength Division Multiplexer Modules Catalog Number VPM - _ _ _ Package Style A _ _ _ Number of Circuits...

Ngày tải lên: 21/12/2013, 08:17

... ADC Coarse Wavelength Division Multiplexing CWDM VAM Module Ordering Guide and Information Catalog Number CW - ... nm, 1530 nm, 1550 nm, 1570 nm, 1590 nm, 1610 with 1310 nm upgrade Page ADC Coarse Wavelength Division Multiplexing CWDM VAM Module Ordering Guide and Information Definition of Variables CW + 1, ... type and amount of ports needed before configuring a catalog number Page ADC Coarse Wavelength Division Multiplexing CWDM VAM Module Ordering Guide and Information Application #1: Ordering a MicroVAM...

Ngày tải lên: 17/01/2014, 11:20

Ngày tải lên: 19/02/2014, 14:20

... a mux (crossbar) from several inputs to several outputs All the inputs are multiplexed using the TDM Time Division Multiplexing For a high throughput, more than one switch can be implemented ... (and the number of clock cycles used to construct the flits) (ii) Adaptor tmd performs the time division multiplexing for the process of cutting one packet to several flits (iii) Adaptor pack adds ... designed with an identical structure and interface given in Figure To run each node at its best frequency, Globally Asynchronous Locally Synchronous (GALS) concept is used in this architecture...

Ngày tải lên: 21/06/2014, 20:20

... described in [13], also denoted as Interleaved Frequency Division Multiple Access (IFDMA) in the original paper [14] or Single-Carrier Frequency Division Multiple Access (SCFDMA) with distributed ... equidistantly frequency- separated blocks, each consisting of a few subcarriers, are allocated to each user A Discrete Fourier Transform (DFT) precoding step is performed on each Orthogonal FrequencyDivision ... good tradeoff in each scenario In this paper, we present a novel multiple access scheme denoted as Block-Interleaved Frequency Division Multiple Access (B-IFDMA), which is intended to fulfill the above...

Ngày tải lên: 21/06/2014, 22:20

... (2) where the notation is defined above Orthogonality between the received cooperation signal yrd and direct signal ysd can be implemented by frequency division (FD) The optimal bandwidth allocation ... algorithm, similarly to [10] This paper is organized as follows: in Section 2, the signal model for the orthogonal relay channel, main assumptions, and notation are given; in Section 3, the proposed QF ... algorithm In this paper, we further extend the iterative algorithm of [9] in the context of quasistatic orthogonal relay channels by taking into account both the forward and backward channels and providing...

Ngày tải lên: 22/06/2014, 00:20

... học Đồ án trình bày công nghệ mới: công nghệ ghép kênh theo bước sóng quang WDM (Wavelength Division Multiplexing) và ứng dụng việc phát triển mạng thông tin quang nhằm tăng dung lượng truyền ... I.1 Giới thiệu: Đặc điểm bật hệ thống ghép kênh quang theo bước sóng quang (WDM: Wavelength Division Multiplexer) là tận dụng hữu hiệu nguồn tài nguyên băng rộng khu vực tổn hao thấp sợi quang ... Optical Network - cấp số đồng bộ/ mạng quang đồng bộ) Các nhà cung cấp DWDM (Density Wavelength Division Multiplexer) sớm phát triển thiết bị nhằm hỗ trợ cho việc truyền nhiều kênh quang Các hệ...

Ngày tải lên: 22/06/2014, 15:19

... 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 ... Time, frequency, and multiuser diversity effects improve the bit error performance The maximum Doppler frequency is normalized to the chip rate The thick lines show the SLP (upper line for frequency- flat ... values for the carrier frequency and the chip duration 6.2 MMSE channel estimation Let us now turn to MMSE channel estimation Numerical bit error results for frequency- flat and frequency- selective...

Ngày tải lên: 22/06/2014, 23:20

... from single-user case They are easily extended to cases with multiple users The outage capacity issue for single-user multiple- input multiple- output (MIMO) case was studied extensively In [1], ... 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 ... applied to multiple- user cases to obtain time-sharing bounds The only difference is that the boundary will be defined by multiple rates and the condition in (19) will be given by the product of multiple...

Ngày tải lên: 23/06/2014, 01:20