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Peach, R. C.

Publications and source records attributed to Peach, R. C..

New developments for SAW channelization for mobile satellite payloads

The use of SAW technology in mobile communication payloads is becoming widely accepted by the industry since being pioneered by Inmarsat for its third generation of satellites. This paper presents new developments in this area, including broadband processors of the Inmarsat 3 type, and the use of SAW filters at L-band. It is demonstrated that SAW processors have considerable potential for increasing the capacity of future communications payloads, while allowing fully transparent operation without any restriction on traffic type or modulation format. In addition to the evolutionary development of Inmarsat type processors, new SAW applications have also emerged recently. Therefore, despite the rapid changes in the industry, it is predicted that SAW processing has a strong future in satellite communications.

Peach, R. C.↗

SAW based systems for mobile communications satellites

Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

Peach, R. C.↗