Accurate personnel and vehicle tracking has been achieved using networks of small, unobtrusive, low-cost wireless sensors. The wireless MSTAR sensors developed in this work are based on previous pioneering MEMS sensing and TinyOS communications software work completed at UC Berkeley. The works has been funded under the DARPA SensIT, SensorWebs, and on-going DARPA NEST programs. These MSTAR sensors deliver around the clock all-weather surveillance and perimeter protection for field environments, including buildings, camp and tent locations, streets, mountainous regions, and other geographies. These capabilities satisfy many on-going intelligence and warfighter safety requirements. The MSTAR sensors are quickly deployed by hand emplacement or air-drop from a UAV or other airborne platform. The combination of multimode sensing on each wireless MSTAR sensor and multiple MSTAR sensors in the environment yields low false detections within the network perimeter. A low-power spread spectrum wireless link is used for communication across the MSTAR sensor network. Satellite exfiltration of data provides real-time access to the data on a worldwide basis. Future work includes additional field trials and the incorporation of acoustic capture, video capture, and biosensors into the MSTAR wireless sensor platform.
Accurate personnel and vehicle tracking has been achieved using networks of small, unobtrusive, low-cost wireless sensors. The wireless MSTAR sensors developed in this work are based on previous pioneering MEMS sensing and TinyOS communications software work completed at UC Berkeley. The works has been funded under the DARPA SensIT, SensorWebs, and on-going DARPA NEST programs. These MSTAR sensors deliver around the clock all-weather surveillance and perimeter protection for field environments, including buildings, camp and tent locations, streets, mountainous regions, and other geographies. These capabilities satisfy many on-going intelligence and warfighter safety requirements. The MSTAR sensors are quickly deployed by hand emplacement or air-drop from a UAV or other airborne platform. The combination of multimode sensing on each wireless MSTAR sensor and multiple MSTAR sensors in the environment yields low false detections within the network perimeter. In addition, using the geopgraphy dispersion and networked algorithms, it is possible to estimate the target's speed, direction, and loosely classify the target. Satellite exfiltration of data provides real-time access to the data on a worldwide basis. Future work includes additional field trials and the incorporation of acoustic capture, video capture, and biosensors into the MSTAR wireless sensor platform.
Described here is an adaptive MAC-layer protocol that supports multiservice (STM and ATM) applications in the context of subscriber access to tree and branch (e.g., fiber-coaxial cable) networks. The protocol adapts to changing demands for a mix of circuit and cell mode applications, and efficiently allocates upstream and downstream bandwidth to a variety of bursty and isochronous traffic sources. In the case of a hybrid fiber-coaxial (HFC) network the protocol resides in customer premises equipment and a common head-end controller. A medium-access control (MAC) processor provides for dividing the time domain for a given digital bitstream into successive frames, each with multiple STM and ATM time slots. Within the STM region of a frame, variable length time slots are allocated to calls (e.g., telephony, video telephony) requiring different amounts of bandwidth. A contention access signaling channel is also provided in this region for call control and set-up requests. Within the ATM region fixed-length time slots accommodate one individual ATM cell. These ATM time slots may be reserved for a user for the duration of a call or burst of successive ATM cells, or shared via a contention process. At least one contention time slot is available for signaling messages related to ATM call control and set-up requests. Further, the fixed-length ATM time slots may be reserved by a user for the duration of a call, or shared through a contention process. This paper describes the MAC-layer protocol, its relation to circuit- and ATM- amenable applications, and its performance with respect to signaling throughput and latency, and bandwidth efficiency for several service scenarios.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.