A novel impulse radio network for tactical military wireless communications

Two of the major concerns in tactical military wireless communication networks are covertness and throughput. Impulse radio is an ultra-wideband code division multiple access (UWB-CDMA) technique being considered as the physical layer for future networks. Impulse radio exhibits low power spectral density and relatively high immunity to fading but suffers from relatively long acquisition times. In traditional packet radio networks (PRNs), the physical layer link is terminated while scheduling half-duplex transmissions or in the absence of data packets. To re-establish physical layer links in an impulse radio system, signaling packets containing exceptionally long acquisition headers transmitted at higher powers are required. Hence, to improve covertness in an impulse radio based network, we propose a MAC layer scheme we call sustained link networks (SLN) where the physical layer links are maintained continuously. We develop a full-duplexing scheme which takes advantage of the low duty cycle nature of impulse radio to maintain physical layer links capable of supporting bi-directional data transfer. During the periods between data bursts, the physical layer links are maintained by transmitting supplementary data at low bit rates and low power levels. We quantify the performance of an impulse radio receiver implementing the full-duplex scheme developed. We also present performance comparisons of an SLN based on impulse radio with traditional PRN variations implemented using impulse radio.