Link search algorithms for a spread-spectrum mobile communication network with directive/adaptive antennas
Tien-Yow Liu, R.A. Scholtz · 2002
A non-centralized fully distributed mobile communication network with directive or adaptive antennas is proposed. Every node uses directive or adaptive antennas for transmitting and receiving communication signals. The spatial and temporal synchronization of the transmitting and receiving antenna beams is accomplished by employing the Global Positioning System (GPS) information and a double-ended spatial search algorithm. This research focuses on the problem of how a communication transmitter (CT) establishes the communication link with a communication receiver (CR). Two link search algorithms, (1) a sequential ascending search power algorithm using an optimal set of link power levels and (2) a sequential Bayesian search algorithm using Bayes rule to up date the CR location information, for additive white Gaussian noise (AWGN) channels, are proposed for a CT to search for its intended CR. A probability of interference, used as performance measurement for link search algorithms, is defined as the ratio of expected number of interfering event to the total number of the un-intended CRs per transmission. Examples and asymptotic analyses of the two link search algorithms employing a realistic antenna pattern are presented.