Laboratory performance of spread spectrum detectors

Abstract

Canada KIA 024 squarer All O(dc) sq-r DSBPSK 2fc Abstruct-The laboratory performance of four spreadspectrum (SS) detectors (full-band and partial-band radiometers, chip-rate detector (CRD) and squaring carrier detector) was measured for direct sequence (DS) and frequency hop (FH) S S signals, FHDS hybrids, and time hop (TH) DS signals. Probability of detection as a function of input SNR for a constant false-alarm rate was measured for numerous combinations of SS waveform and detector. Theories were compiled from the literature and extended as necessary to provide a unified theoretical description. The results usually agreed with theory to within one dB. A constant-false-alarm-rate method was used to reduce the drift problem of radiometers. The fact that chip-rate and squaringcarrier detectors have a much reduced drift problem was confirmed. It is concluded that the four SS detectors used are relatively simple and inexpensive devices with laboratory detection performance close to theoretical. 28.6-1 785 7803-9828-5194 $4.00 0 1994 IEEE

Detection range of energy and feature detectors based upon communicator link budgets

“…1 It is shown in [5], based on standard literature, that if 2TW >> 1, then a Gaussian approximation can be used and the probability of detection is…”

“…It is noted in [5] and elsewhere that for a constant P f , P d given by (1) takes on a characteristic stretched "S" shape that starts with P d ! P f for low SNR out , followed by a rapidly rising transition region, finally approaching 1.0 for values of SNR out a few dB above the transition region.…”

“…In [4], link budget considerations are employed for examining detection of frequency-hopped multiple-access systems. The extension to the specialized detectors is summarized in [5]. In the present paper, two rules of thumb are combined with linkbudget analysis to provide a simple means to determine the detection range.…”

Performance of a Digital Ad-Hoc Chip Rate Estimator (ACRE) Given a Direct Sequence Spread Spectrum Pulse Shaped Signal

“…One possible implementation of the CRD is shown in Figure 1 [2]. From the diagram it is clear that certain knowledge of the signal must be known or estimated prior to the CRD producing the desired results.…”

“…The theoretical and laboratory performance of a chip rate detector (CRD) is well documented for rectangular pulse shapes [1][2]. The second section of the paper will discuss the CRD, the a priori signal knowledge needed for operation, and a simple analysis of the degradation of the CRD performance due to half-sine shaped pulses verses rectangular pulses.…”