Abstract: High quality communications among a diverse set of cognitive radio (CR) nodes is permitted while minimizing interference to primary and other secondary users by employing Dynamic Spectrum Access (DSA) in a Dynamic Cellular Cognitive System (DCCS). Diverse device types interoperate, cooperate, and communicate with high spectrum efficiency and do not require infrastructure to form the network. The dynamic cellular cognitive system can expand to a wider geographical distribution via linking to existing infrastructure.

Abstract: High quality communications among a diverse set of cognitive radio (CR) nodes is permitted while minimizing interference to primary and other secondary users by employing Dynamic Spectrum Access (DSA) in a Dynamic Cellular Cognitive System (DCCS). Diverse device types interoperate, cooperate, and communicate with high spectrum efficiency and do not require infrastructure to form the network. The dynamic cellular cognitive system can expand to a wider geographical distribution via linking to existing infrastructure.

Abstract: A random access technique for one way channels. With the apparatus and method of this system, each user sends an initial message of stated length to a central receiver. The message is then retransmitted a specified number of times in a pre-determined interval reserved for the retransmission process. The time interval between each successive retransmission of a given message is randomly generated. The random access protocol with retransmissions improves the probability of successful message transmission in a one way communication environment where observation (retransmission) periods for all users do not overlap.