1. A method for improving the spectral efficiency and scalability of a Mobile Ad-Hoc Networking (MANET) system, comprising: a) at each node, providing a transceiver architecture that includes a combination of a transmitter being capable of dynamically selecting its channel frequencies within the whole operational RF band assigned to said system and a wideband receiver that is being capable of simultaneously receiving and processing signals received from nodes of said MANET in different frequency channels within the whole operational band assigned to said system, at once, and that includes channel frequencies, dynamically selected within a wide operating bandwidth; b) allowing each node to simultaneously receive all other nodes which are in range within the whole operating band assigned to said system such that each of the remaining nodes determines the transmission frequency for each time slot; for each transmitting node c) finding time slots, in which a counterpart transceiver at each remaining active node is not transmitting and a frequency channel in which no other active node, neighboring said counterpart receiver, transmits; and if no other node had chosen the same time slot, and if the transceiver is not transmitting in said slot, receiving the transmission, while allowing relay nodes to transmit simultaneously, using different channels, wherein the decision which node in the MANET should transmit is made independently and separately for each time-slot.