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Adaptive Transmission Protocols For Wireless Communication Systems With Fountain Coding, Jason Ellis
Adaptive Transmission Protocols For Wireless Communication Systems With Fountain Coding, Jason Ellis
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We present low-complexity adaptive protocols for both unicast and multicast transmission in wireless communication systems that employ higher layer fountain codes. Our adaptive protocols respond to variations in channel conditions by adapting the modulation and channel coding of transmitted packets, and they provide efficient communication over wireless channels that experience fading, shadowing, and other time-varying propagation losses. The operation of our protocols is governed by simple receiver statistics that can be obtained during the demodulation of received packets. We present three adaptive protocols for fountain-coded unicast transmission, and compare the throughput performance of our protocols with that of fixed-rate systems, …
Cross-Layer Scheduling Protocols For Mobile Ad Hoc Networks Using Adaptive Direct-Sequence Spread-Spectrum Modulation, Brian Wolf
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We investigate strategies to improve the performance of transmission schedules for mobile ad hoc networks (MANETs) employing adaptive direct-sequence spread-spectrum (DSSS) modulation. Previously, scheduling protocols for MANETs have been designed under the assumption of an idealized, narrowband wireless channel. These protocols perform poorly when the channel model incorporates distance-based path loss and co-channel interference. Wideband communication systems, such as DSSS systems, are more robust in the presence of co-channel interference; however, DSSS also provides multiple-access capability that cannot be properly leveraged with a protocol designed for narrowband systems. We present a new transmission scheduling protocol that incorporates link characteristics, spreading …