Abstract: A system and method for generating a low probability of detection (LPD) waveform is presented. The method modulates pre-modulated symbols using pulse-position modulation (PPM) to produce PPM modulated signals with a modulated in-phase (I) component and a modulated quadrature (Q) component. Next, frequency hopping is used to transmit the modulated I component at a randomized start time within a time slot and to transmit the modulated Q component at the randomized start time within the same slot. The modulated Q component does not overlap with the modulated I component. The method can also overlay transmission security (TRANSEC) pseudorandom (PN) overlay on the modulated Q component and the modulated I component before the modulated Q component and the modulated I component are transmitted.

Abstract: A CDMA format is used within a network to permit communication between members of a network. Network members are synchronized to each other and are each aware of a predetermined set of code words which has been established. A member desiring to transmit data selects a code word from the predetermined set. If there are unused code words, one of the unused words is randomly selected. If all words are being used, the code word of the farthest user is selected. Since all members are synchronized in time to stable clocks, the range of each user is known. All members of the network are always listening and keeping track of detections of other users and code words. Transmitted signals are a series of pulses with a jitter or sync pulse inserted within each series. The number and location of sync pulses is unique for each code and defines the CDMA code of the signal.