Wireless địa phương vòng - lý thuyết và ứng dụng P6 ppt

... expected simply due to conventional path loss analysis. There- fore, in many cases with the omni-directional antenna, a quasi-line-of-sight (QLOS) existed in which a strong specular reflector lead ... ruggedized single- mode fibre. Single-mode fibre has extremely low loss (0.02 dB/km) and low dispersion for the frequency range of interest. A high-speed photo-detector converted the light- wave...

Ngày tải lên: 01/07/2014, 20:20

... codec: 64 kbps PCM (ITU-T G.711), 32 kbps ADPCM (ITU-T G.726), 16 kbps LD-CELP (ITU-T G.728), and 8 kbps conjugate structure algebraic-code-excited linear prediction (CS-ACELP, ITU-T G.729). However, ... 1997. [11] TIA/EIA/IS-95-A, Mobile Station-Base Station Compatibility Standard for Dual-Mode Wide- band Spread Spectrum Cellular System, 1995. [12] ANSI J-STD-008, Personal Station-Base Stati...

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... 9.4. H FS H BS,k H U,K d FS-BS, A d FS-BS, k d FS-U,k d FS-U,k r FS-BS, k r FS- U,k r BS, A-BS, k r FS-U,K r FS-BS, A q FS-U,k q FS-BS,k Main Lobe Axis FS-ML B-Cell A-Cell Tier of cell 'B' One Sector Coordinate system ... asynchronous operation may be performed. . Coherent spreading-code tracking. . Fast transmit power control on both mobile-to-cell-site and cell-site-to-mobile link...

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... analogue to digital cellular, like AMPS, IS-95 CDMA and IS-136 TDMA and low-tier PCS such as Cordless Telephone-2 (CT-2), Digital Enhanced Cordless Tele- communications (DECT) to proprietary systems. 2.3 ... Models for Wireless Local Loops Office Wireless Base station Wireless Base station Local Exchange Local Exchange Inter- Exchange switching Residential Houses Figure 2.1 Configurati...

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... J., vol. 10, no. 5, pp. 229±235, Oct. 1998. [19] `ATM Radio-in-the-Local-Loop (RL/A),' in Proceedings of the Wireless Broadband Commu- nications Workshop, 1997, Brussels, Belgium, Sep. 29. [20] ... point-to-point link is formed between the stations (see Figure 3.8), so reducing the delay spread com- pared to the one in case 3. Another advantage is the increase in coverage obtained from...

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... consideration, a computer simulation based on Finite-Difference-Time Domain (FD-TD) [12] technique is adopted. The Finite- difference-Time Domain (FD-TD) formulation is a convenient tool for solving 88 ... practical medium para- meters. The performance analysis of the combined system is carried out through the evaluation of signal-to-quantization noise ratio (SQNR) versus signal-to-noise rati...

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... for in-building wireless systems), home office (SOHO) and residential market with increasing commu- nication needs. This is a cost sensitive market with voice being the primary communica- tion ... Frenkiel and T. Imielinski, `Infostations: The Joy of ``Many-time, many-where'' Commu- nications,' WINLAB Technical Report TR-119, Apr. 1996. [4] D. Goodman, J. Boras, N. B. Mandaya...

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... between multiple wireless conversations [10]. Its bandwidth is much wider than that required for simple point-to-point commu- nications at the same data rate because it uses noise-like carrier waves ... Mobile Commu- nications (GSM), and Personal Digital Cellular (PDC). 7.3.2 Code Division Multiple Access CDMA is a form of spread-spectrum, an advanced digital wireless transmission tech- n...

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... as co-channels. The co-channel re-use distance s denotes the minimum distance for re-use of the channel with an acceptable level of interference. A channel can be reused by a number of co-channels ... respective RNTs. Broadcast-phase signalling period signalling period fixed length signalling period Uplink-phase transceiver turn-around interval time Rand acc. Downlink-phase Figure 8.2 Structu...

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... processor baseband processor baseband processor Traffic generator AP RF RFRF R-FR CTL CTL CTL T-FR T-FR T-FR STA 2 STA 1 R-FR R-FR video TE (MPEG II) video TE (MPEG II) MAC&DLC processor baseband processor RF CTL T-FR STA 3 R-FR voice TE (PCM) MAC&DLC processor baseband processor RF CTL T-FR STA ... TE (PCM) MAC&DLC processor baseband processor RF CTL T-FR STA 5 R-FR data TE (LANE...

Ngày tải lên: 01/07/2014, 20:20