Distributed successive approximation coding using broadcast advantage: The two-encoder case

Abstract

Abstract-Traditional distributed source coding rarely considers the possible link between separate encoders. However, the broadcast nature of wireless communication in sensor networks provides a free gossip mechanism which can be used to simplify encoding/decoding and reduce transmission power. Using this broadcast advantage, we present a new two-encoder scheme which imitates the ping-pong game and has a successive approximation structure. For the quadratic Gaussian case, we prove that this scheme is successively refinable on the {sum-rate, distortion pair} surface, which is characterized by the ratedistortion region of the distributed two-encoder source coding. A potential energy saving over conventional distributed coding is also illustrated. This ping-pong distributed coding idea can be extended to the multiple encoder case and provides the theoretical foundation for a new class of distributed image coding method in wireless scenarios.

Share risk and energy: Sampling and communication strategies for multi-camera wireless monitoring networks

“…By interleaving the sampling time of cameras, we find the optimal sampling configuration to maximize the event detection probability. This is also related to our previous work on successive refinement coding of two static sources [4] [5], where two cameras cooperate in a Ping-Pong fashion to achieve joint successive refinement coding of stereo-view images. Our proposed scheme in this paper can be thought as an extension from two cameras to multiple cameras, as well as from static images to video streams.…”

“…Motivated by the successive refinement coding of two static sources [4], we extend this scheme to encode videos 1 from n cameras: each camera samples at frequency f /n, and the sampling time of cameras are arranged in an interleaved manner, imitating a single camera sampling at frequency f . In this way, we distribute the risk of physical hazard and energy burden of wireless transmission into n independent cameras, while the overall event detection capability is kept the same.…”