space division multiple access in wireless communication

... they jointly define the multiple-access capacity region under the fading condition H As a result of the definition, the rate pairs inB1(p) andB2(p) only satisfy the constraint on the individual ... correspond-ingR2by solving (35) numerically using the expressions ob-tained forT2andT3in the appendix Although the approach used in this section may, in principle, also be applied to multiple-mobile ... fading condition, that the capacity region should increase linearly in each dimension asρ increases lin-early in dB As a result, we would also expect the outage ca-pacity region to increase linearly

Ngày tải lên: 23/06/2014, 01:20

... used in a reference subchannel in a reference cell are distributed in different subchannels in the reuse cells The subcarriers used in a subchannel in a certain cell are unlikely to be repeated in ... MAPPING FROM SUBCARRIERSUSE OF OFDMA IN WIMAX AND LTE Subcarriers are the smallest granular units in the frequency domain, OFDM symbol duration is the smallest granular unit in the time domain in ... University Orthogonal Frequency Division Multiple Access in WiMAX and LTE: A Comparison Group 4 – Trang 2 INTRODUCTION USE OF OFDMA IN WIMAX AND LTE  NETWORK ENTRY STEPS IN WIMAX AND LTE  PERFORMANCE

Ngày tải lên: 24/07/2015, 22:26

... cập nhật các thông tin này sử dụng các bản tin tin cậy được định nghĩa theo tiêu chuẩn Dựa trên điều này, trạm gốc sẽ chọn 2 bin trong một trong số các băng và phân bố những bin như vậy cho 3 ký ... kề nhau được sắp xếp trong một nhóm, được gọi là các bin, như trong hình 5 Mỗi bin có 8 sóng mang dữ liệu và một sóng điều khiển, và 4 bin liền kề thì được nhóm vào một band Người dùng gửi dữ ... fading lựa chọn, [4] Ngoài ra, tần số đa dạng và kênh thông tin phản hồi có thể được sử dụng hiệu quả để cải thiện sức mạnh và thông lượng [4] Do đó, (OFDM) được ưu tiên trong hệ thống thông tin

Ngày tải lên: 24/07/2015, 22:27

... MAI multiple access interference TDMA time division multiple access MF matched filtering WiMAX worldwide interoperability microwave access Trang 10Summary In current broadband evolution of wireless ... Division Multiple Access (FDMA), becomes a paramount candidate to support multiple access in future broadband wireless systems due to its advantages over existing multi-access techniques In uplink ... Interference Suppression in OFDMA Uplink 9 1.4 Outline 12 Chapter 2 Inter-Carrier Interference in OFDMA System Uplink 13 2.1 Frequency Asynchronism and ICI in OFDMA Uplink 13 2.2 A Review

Ngày tải lên: 14/09/2015, 14:03

... by reducing the chances of transmission for the sending stations in the way of increasing the minimum conten-tion window size The downlink compensaconten-tion access (DCA) algorithm in [16] gives ... contents-providing services, presence services, and E-911 locating services, have recently been drawing much attention in wireless network community Since LBSs rely on the location information in providing ... serSer-vices, intelligent traffic alerts, tracking, pinpointing child’s location, and local map pro-visioning have been dealt with much attention in the community [2-4] Noticeable point is that

Ngày tải lên: 20/06/2014, 22:20

... estimation schemes suitable for interleave-division multiple access (IDMA) systems are presented Training and data are superimposed Training-based and semiblind linear channel estimators are derived ... the result to joint estimation of multiple channels with a combined knowledge of pilot data and soft chips (which can be interpreted as “virtual” training), we obtain semib-lind joint least-squares ... method is therefore well suited for estimating fast-fading channels In this paper, we apply superimposed train-ing to IDMA Superimposed traintrain-ing for IDMA is particu-larly simplified by

Ngày tải lên: 22/06/2014, 23:20

... power spent in the sensing state In fact, in our protocol, the time during which sensors are in a sens-ing state is high, so if in this state they spend the same en-ergy as in the receiving state ... ROUTING PROTOCOL—LEACH B+ We propose a new routing strategy which combines LEACH B [18] with a simple single-path routing protocol, which in-cludes the direct transmission to the final sink, ... point out that the random changing of the CHs can mitigate the hidden terminal problem In fact, in every round in LEACH B+ v1, or every two rounds in LEACH B+ v2, the clusters change according

Ngày tải lên: 23/06/2014, 00:20

... 1. Multiuser Communications 1 1.1 Conflict-Free Medium Access Control 2 1.1.1 Time Division Multiple Access 3 1.1.2 Frequency Division Multiple Access 5 1.1.3 Code Division Multiple Access 6 1.1.4 ... 2.8 Multiple Access Performance of Frequency-Hopped Code Division Multiple Access 67 2.9 Summary 71 3. Cellular Code Division Multiple Access 73 3.1 Principles of Cellular Code Division Multiple ... techniques such as time division multiple access and frequency division multiple access. Additionally, random access schemes such as carrier sense multiple access are examined. In Chapter 2, basic

Ngày tải lên: 27/06/2014, 14:20

... sharing of a single frequency band and time slot The first principle that we will discuss is interference averaging Recall that in-band interference is inevitable in all wireless systems In TDMA/FDMA ... is spreading gain The despreading process mitigates the interference that any one signal causes to another signal As a result, in CDMA, we increase the number of interfering signals in exchange ... cellular CDMA systems MULTIPLE ACCESS In this section, we will discuss four key principles of CDMA systems, particularly cellular systems: interference averaging, statistical multiplexing, universal

Ngày tải lên: 07/08/2014, 21:20

... and the coverage area Increasing the number of users in the system increases the uplink interference, which, if a target Eb /I0is to be maintained, requires an increase in the mobile transmit ... By inserting values, we can determine the expected value through numerical integration For example, forκ = 4, ν = 3/8, andσ = 8dB, we obtain [42] E  I P  Trang 490 CODE DIVISION MULTIPLE ACCESS ... (3.44) and summing overϕ i, we have the constraint K i=1 ϕ i ≤ β B T /R b (Eb /I0)req − K i=1  N P T i Trang 692 CODE DIVISION MULTIPLE ACCESS (CDMA)Defining the right-hand side of the inequality

Ngày tải lên: 07/08/2014, 21:20

... control. Trang 4CELLULAR CODE DIVISION MULTIPLE ACCESS 109to the system, the admission control process examines the increase in cell interference at the current load If the new interference level exceeds ... decreased by reducing the transmit pilot strength or by increasing the uplink interference level As mentioned previously, as the system load increases, the cell size naturally shrinks since far away ... to multipath fading, ability to reject narrowband interference (e.g., jamming), low probability of detection or intercept, and enhanced multiple access capabilities Additionally, in distributed

Ngày tải lên: 07/08/2014, 21:20

... orbiting satellites offering continental and worldwide communications, data, tracking, and paging services. The experience gained from these networks in the next few years will provide valuable input ... and NMT 900 in Europe; European Total Access Communication System (ETACS) in the United Kingdom; C-450 in Germany; and Nippon Telephone and Telegraph (NTT), JTACS, and NTACS in Japan. In contrast ... James Llinas Handbook of Antennas in Wireless Communications Lal Chand Godara Forthcoming Titles Propagation Data Handbook for Wireless Communications Robert Crane The Digital Color Imaging Handbook Guarav...

Ngày tải lên: 18/04/2014, 11:02

... techniques in wireless communications. Chapter 2 conducts a thorough review of the initial synchronization techniques applied to wireless orthogonal-frequency -division- multiplexing (OFDM) communications. ... (SCTP) in wireless communication networks. Chapter 13 investigates traffic control for composite wireless access route of IEEE802.11/16 links. Recent Advances in Wireless ... st st IE θ θ θ θ θ θσ − = ⎧⎫ ∂ ∂ ⎪⎪ ⎛⎞ =− ∑ ⎨⎬ ⎜⎟ ∂ ∂ ⎝⎠ ⎪⎪ ⎩⎭ (16) Finally, the inverse recipocal of the Fisher‘s information produced by the CRLB in the AWGN channel. X Preface engineers to beginning or professional researchers. All interested...

Ngày tải lên: 19/06/2014, 19:20

... higher in multicarrier communications than in single carrier communications because of intersymbol interference. The mismatch or instability of the local oscillator inevitably causes an offset in ... Advances in Wireless Communications and Networks 32 () { } 2 1 ˆ argmax p θ θλθ ′ = (17) In addition, several techniques for combining multiple frames have also been investigated (Lin, 2003) ... 2.2.1 Timing offset OFDM systems exploit their unique features by using a guard interval with a cyclic prefix to eliminate intersymbol interference and intercarrier interference. In general,...

Ngày tải lên: 19/06/2014, 19:20

... Will-be-set-by -IN- TECH Spatial stream parser Input bits STBC Symbol mapping Segment S/P Grouping Spreading GO-CDM Symbol mapping Segment S/P Grouping Spreading GO-CDM Antenna mapping CDD IFFT CP CDD ... Limits of Wireless Communications in a Fading Environment when Using Multiple Antennas. Wireless Personal Communications, Vol.6, No.3, (March 1998), pp.311-335, ISSN 0929-6212. Foschini, G. ... therein), it is the application of multiple antenna at the transmitter side what revolutionised the wireless community. In particular, the linear increase in capacity achieved when jointly increasing...

Ngày tải lên: 19/06/2014, 19:20

... length in a lattice, including a complexity analysis, Math. Comput. 44: 463–471. Foschini, G. (1996). Layered space- time architecture for wireless communication in a fading environment when using ... Division Multiple Access) . OFDMA is one of the principal multiple access schemes for broadband wireless multiuser systems. It has being proposed for use in several broadband multiuser wireless ... corresponding users’ rate vector are obtained from (8) and shown in Fig. 6 as a marker point in the boundary of the rate region. Therefore, the marker points are the points of R 0 located in the...

Ngày tải lên: 19/06/2014, 19:20