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Abstract
Multipath communications signal impairment is a result of multiple waves constructively and destructively combining along the radio waves path. In any communications system, multipath propagation presents some of the most challenging problems for designing a mobile communications system. The issues of multipath problems to a communication system show up as delay spread and Raleigh fading. Multipath has many positive characteristics in mobile radio communication because it allows for radio waves to bend around objects. Delay spread time dispersion is a result of multipath for a digital radio system. Dispersion occurs when multiple signals arrive at different times to the receiver, and the difference in time between the signals arriving are on the order of a bit period. The solutions used to combat multipath and delay spread are the introduction of a fade margin, diversity, additional cell sites, voice coding, modulation techniques, employing adaptive equalizers, and error correction.