Constructions of specific permutation codes for multi-user communication

Regular constructions for specific permutation codes used in a multiple-access OR channel where the inputs originate from a fast frequency hopping/multiple frequency shift keying modulation are presented for 3 situations : (1) each sender is either active or passive; (2) the jammer is allowed to corrupt a certain number of transmitted frequencies; and (3) the sender transmit one of a certain number of messages. We show that these constructions are optimum ones for the situations (1), (2) and that they are close to the optimum for the situation (3)