MIMO-OFDM WLAN Architectures, Area Coverage, and Link Adaptation for Urban Hotspots

• Published in: IEEE transactions on vehicular technology Vol. 57; no. 4; pp. 2364 - 2374
• Main Authors: Bian, Y.Q., Nix, A.R., Tameh, E.K., McGeehan, J.P.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.07.2008; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive arrays; Algorithms; Applied sciences; Business and industry local networks; Coding, codes; Exact sciences and technology; Frequency division multiplexing; Information, signal and communications theory; Link adaptation (LA); MIMO; Modulation coding; Modulation, demodulation; Multiplexing; Networks and services in france and abroad; orthogonal frequency-division multiplexing (OFDM); Physical layer; power control; propagation; Radio link; Ray tracing; Samarium; Signal and communications theory; space-time block codes (STBCs); spatial multiplexing (SM); Telecommunications; Telecommunications and information theory; Teleprocessing networks. Isdn; Throughput; Wireless communications; Wireless LAN; Spatial Multiplexing; Space Time Block Codes; Power Control; Link Adaptation; OFDM; Propagation; Block code; Wireless LAN; Space-time codes; Hot spot; Wireless telecommunication; space-time block codes (STBCs); Information rate; Urban area; Spatial multiplexing; spatial multiplexing (SM); Ray tracing; Localization; Adaptive modulation; Modulation coding; orthogonal frequency- division multiplexing (OFDM); Antenna; MIMO system; Radio link; Power electronics; Space time; Algorithm; Information transmission; Adaptive coding; propagation; Power control; Orthogonal frequency division multiplexing; Link adaptation (LA)
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2007.909289

This paper considers the suitability of a range of multi-input-multi-output (MIMO) orthogonal frequency-division multiplexing architectures for use in urban hotspots. A ray-tracing propagation model is used to produce realistic MIMO channel data. This information is used to determine the expected throughput and area coverage for various physical (PHY) layer schemes. Site-specific throughput predictions are generated in a city-center environment. Link adaptation (LA) is shown to play a key role in the choice of space-time algorithm, the use of adaptive modulation and coding, and the number of antennas employed at both ends of the radio link. No single PHY layer scheme is suitable to cover the entire coverage area. Results demonstrate the need for MIMO LA under a wide range of channel conditions. For the area under test, 2% of covered locations selected a spatial multiplexing (SM) scheme, 50% selected a space-time block coding (STBC) scheme, and 48% selected a hybrid SM/STBC scheme. With suitable power control and LA, for the scenario under consideration, high peak capacities and good geographic coverage were achieved.