Browsing International Telemetering Conference Proceedings, Volume 42 (2006) by Title
Now showing items 81-84 of 84
WHAT IF T&E HAD INFINITE SPECTRUM?The availability of spectrum has been decreasing while requirements have been increasing. One way of answering the question of how much impact this has is to ask how much spectrum would be used in an ideal situation. A way of getting a handle on this question is to look at how much data is recorded onboard test vehicles. We can assume that, if we could, we would transmit everything we currently record. This would be ideal since we could then consider the onboard recorders as backup and we would have all data available in case of catastrophe. This paper looks at onboard recording and telemetry trends to see what percentage of data has been and will be telemetered. This analysis involves several levels in that telemetry requirements are not limited to transmission over a single frequency. It is common to have more than one vehicle involved in an operation. Thus, different scenarios are evaluated from single vehicle operations to larger scale test and training operations. When considered from this point of view, the impact becomes quite clear: the T&E community is making significant compromises on telemetering data. Therefore, current efforts to obtain more spectrum for telemetry use through the World Radio Conference are well justified.
WIRELESS INFRA-RED SENSORFor several decades, the military has used the Multiple Integrated Laser Engagement System (MILES) with a series of iR sensors along a belt fastened to a vehicle for training and simulation. Now, an alternative to this legacy system, a solar rechargeable battery powered wireless IR sensor is replacing wired sensors. The use of short-range RF communications network, allows the MILES sensors strategic placement about a combat vehicle without the umbilical cabling normally required for power and signal coupling from the players processing unit. The RF network operates in the 340 to 380 MHz band, has channeling capability of over 1600 channels, and coexists with the vehicles on board high-powered radios without interference. The wireless sensor implements a custom designed IR sensing amplifier, designed for maximum sensitivity and minimal power dissipation, along with advanced semiconductor IC’s for signal processing and power conversion. Solar recharging enables the sensor to operate for extended time, on a single battery that should last for years without replacement. A proprietary software protocol, developed for communication integrity, is a critical part of the overall system and supports other sensor types and control elements with low data rates for a wireless Vehicle Area Network. The system, successfully installed on several military training platforms, proves to be a viable product for military training and simulation systems for the 21st century.
Wireless Sensor System for Airborne ApplicationsAdding an instrumentation / telemetry system to a test vehicle has historically required an intrusive installation for wiring and powering all elements of the system from the sensor to the telemetry transmitter. In some applications there is need for a flexible and modular instrumentation and telemetry system that can be installed with minimal intrusiveness on an aircraft without the need for permanent modifications. Such an application may benefit from the use of a miniaturized, inexpensive network of wireless sensors. This network will communicate its data to a central unit installed within the aircraft. This paper describes recent efforts associated with the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the challenges in developing a wireless sensor network system for use in an airborne environment. These include selection of frequencies, COTS wireless devices, batteries, system synchronization, data bandwidth calculations, and mechanical structure for external installation. The paper will also describe the wireless network architecture as well as the architecture of the wireless sensor and the central control unit.
XidML – Two Years OnIn 2004 ACRA CONTROL introduced XidML as a published standard for instrumentation definition via XML. After two years in the field, much feedback and two revisions, this paper outlines where the standard is now, some of the lessons learned and discusses some ideas for where next. XidML allows any package, message or frame to be defined including PCM, MIL-STD- 1553, Ethernet and storage formats, it is also used to define the settings for instrumentation as diverse as Analog to Digital modules, MIL-STD-1553 monitors, PCM encoders, recorders, bit-syncs, and decoms. Importantly it facilitates the EU range and data format to be defined for large parameter lists. The key elements in the standard are discussed along with some lessons learned.