Kiến trúc phần mềm Radio P9 pptx

... algorithms and hardware can yield benefits (or cause problems) for the analog parts of the software radio. III. SDR APPLICATIONS ADC and DAC applications are constrained by sampling rate and dynamic range. ... A cellular uplink, for example, might consist of 25 MHz from 824 to 849 MHz. The ideal software radio would convert directly from RF at a sampling rate of say 2.3 GHz. The Nyquist f...

Ngày tải lên: 01/07/2014, 10:20

... to be radio- aware so that the radio s low data rates, high variability in data transfer times, and occasional outages do not severely curtail user satis- faction with the services. In the radio ... approaches, the radio applications and infrastructure software elements are intricately interwoven. Open-architecture approaches now favor the use of the industry-standard CORBA [216] in ra...

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... Call EXERCISES 287 2. Consider a wideband radio that implements frequency hopping with a fast-hopping LO. What steps are necessary to migrate that implementation toward a software -radio architecture? What benefits ... context. A SPEAKeasy-like radio may have to operate within a kilometer of a high-power (90 dBm) troposcatter communications system. Metal structures may reflect some of th...

Ngày tải lên: 01/07/2014, 10:20

... with longer reach and greater reliability than analog radios. A first implementation of an SDR may not perform as well as the equiv alent analog radio because in- adequate attention is paid to the ... that general-purpose processors cannot be used for software radio research. For example, MIT has used the DEC Alpha chip for their virtual radio [178]. DSP teams apply skill in the use of...

Ngày tải lên: 01/07/2014, 10:20

... Interconnect), 316, 320 Radar, 74, 75 Radio applications (layer), 377, 380–380 Radio horizon, 83 Radio infrastructure, 164, 211, 363–368, 378, 380–381 Radio noise, 81, 397 Radio platform (reference model), ... Programmable Digital Radio (PDR) Case Studies 215 A. A Basic Commercial PDR 215 B. Multimode Conventional Radios 218 C. GEC’s Programmable Digital Radio 220 D. ITT Digital...

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Ngày tải lên: 01/07/2014, 10:20

... other. Each radio has LOS access to a point in the troposphere from which radio waves are scattered beyond LOS. Due to the weak coupling between the radio waves and the troposphere, the radios employ ... programmable digital radios. These radio suites also monitor emergency channels using ded- icated transceivers. This includes simultaneous VHF and UHF operation. Illustrative discrete...

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... or more radios each) 500–3000 National Guard troops 50–300 squad radios, 12–80 company radios, 3–10 high-level command network radios, radio relays with 20–50 aircraft 20–50 air mobile radio nodes ... characterizes the expected parameters of that radio channel. All these are necessary in the analysis of software -radio architecture. A. Radio Resource Management Radio resources cons...

Ngày tải lên: 01/07/2014, 10:20

... inheritance re- lationships from the generic radio node class o f object. The domain (e.g., handset, cell site, vehicular radio) property of the radio node is therefore in- herited by the function, ... interface. Layer 1 services are provided in the radio front end. The architecture accommodates multiple layer 1 services corresponding to the radio modes of the SDR. Thus, for example,...

Ngày tải lên: 01/07/2014, 10:20

... disaster-relief case study? 252 ANTENNA SEGMENT TRADEOFFS bands. Using typical military radios such as SINCGARS, these radios will jam each other. Operational steps may reduce the number of networks ... 7-1. Due to the software radio s ability to concentrate energy, software constraints may be required to preclude unacceptable exposure levels. For example, a four-channel radio might be per...

Ngày tải lên: 01/07/2014, 10:20