• ENHANCING THE PCM/FM LINK - WITHOUT THE MATH

      Fewer, Colm; Wilmot, Sinbad; ACRA CONTROL INC (International Foundation for Telemetering, 2007-10)
      Since the 1970s PCM/FM has been the dominant modulation scheme used for RF telemetry. However more stringent spectrum availability as well as increasing data rates means that more advanced transmission methods are required to keep pace with industry demands. ARTM Tier-I and Tier-II are examples of how the PCM/FM link can be enhanced. However these techniques require a significant increase in the complexity of the receiver/detector for optimal recovery. This paper focuses on a quantitative approach to improving the rate and quality of data using existing PCM/FM links. In particular ACRA CONTROL and BAE SYSTEMS set themselves the goal of revisiting the pre-modulation filter, diversity combiner and bit-sync. By implementing programmable adaptive hardware, it was possible to explore the various tradeoffs offered by modifying pulse shapes and spectral occupancy, inclusion of forward error correction and smart source selection. This papers looks at the improvements achieved at each phase of the evaluation.
    • EVALUATING IEEE 1588 IN A HOMOGENOUS SWITCHED NETWORK TEST ARTICLE SEGMENT

      Wilmot, Sinbad; Corry, Diarmuid; ACRA CONTROL INC (International Foundation for Telemetering, 2007-10)
      At the 2007 iNet Technology Demonstrator multiple vendors are asked to participate to develop and evaluate protocols for time synchronization, configuration identification and heterogeneous data packet transfer. The iNet initiative from RCC is aimed at focusing and collating telemetry network developments within the wider sphere of commercial and military network developments. The KAM-500 is an inherently networked data-acquisition system offering seamless gateways to many heterogeneous data sources, such as different sensor devices, avionics-busses, networks and video sources. This paper offers insights into the impact of traffic and network configuration on the performance of heterogeneous data acquisition in a homogenous-switched network based a 1588 enabled controller module.