Communication under Strong Asynchronism

We consider asynchronous communication over point-to-point discrete memoryless channels without feedback. The transmitter starts sending one block codeword at an instant that is uniformly distributed within a certain time period, which represents the level of asynchronism. The receiver, by means of a sequential decoder, must isolate the message without knowing when the codeword transmission starts but being cognizant of the asynchronism level. We are interested in how quickly can the receiver isolate the sent message, particularly in the regime where the asynchronism level is exponentially larger than the codeword length, which we refer to as ‘strong asynchronism.’ This model of sparse communication might represent the situation of a sensor that remains idle most of the time and, only occasionally, transmits information to a remote base station which needs to quickly take action. Because of the limited amount of energy the sensor possesses, assuming the same cost per transmitted s...

• Type: Journal
• Year: 2007
• Where: CORR
• Authors: Aslan Tchamkerten, Venkat Chandar, Gregory W. Wornell
• Keywords: Asynchronism Level, Codeword, Codeword Length, CORR 2007, Education