On Optimal Signaling and Jamming Strategies in Wideband Fading Channels

We investigate the fundamental limits on communication performance in wideband fading channels, in the presence of a jammer. We show that energy-limited Gaussian jammers cannot affect the error exponents in the wideband regime. However, if the sender uses an impulsive training scheme, which is close to optimum in the wideband regime, the jammer may be able to interfere with sounding signals if the location of those signals is known. In the latter case, the jammer significantly reduces the wideband capacity limit