Learn More
In this paper, we present the true Cramér–Rao lower bounds (CRLBs) for the estimation of phase offset for common quadrature amplitude modulation (QAM), PSK, and PAM signals in AWGN channels. It is shown that the same analysis also applies to the QAM, PSK, and PAM CRLBs for frequency offset estimation. The ratio of the modulated to the unmodulated CRLBs is(More)
STUDY OBJECTIVE To determine the sleep/wake habits of patients diagnosed as having obstructive sleep apnea (ie, respiratory event index [REI] > or = 5). DESIGN Case series with prospective data collection to determine the relationship among sleepiness, REI, and sleep/wake habits. Patients were grouped according to their multiple sleep latency test (MSLT)(More)
The true Cramér–Rao lower bound (CRLB) is derived and evaluated for the estimation of carrier phase of Star 16-quadrature amplitude modulation (QAM) and can be simply applied to carrier frequency estimation. Different geometries are investigated by varying the ring ratio (RR). For signal-to-noise ratios (SNRs) between 6–15 dB, the CRLB with RR= 3 is lower(More)
This paper presents an investigation of ISAR image classification based on a comparison of range-Doppler imagery to 3D ship reference models. This comparison is performed in the image domain by estimating the motion of a sequency of ISAR images, generating 3D reference models corresponding to the same motion and matching the models with the given ISAR(More)
Atmospheric acoustic tomography is used to estimate the 2 or 3 dimensional spatial distribution of temperature and wind in the Atmospheric Boundary Layer. Some applications of these results are atmospheric research, boundary layer meteorology, theories of atmospheric turbulence and wave propagation through a turbulent atmosphere. The tomographic technique(More)
This paper addresses the problem of improving the spurious free dynamic range (SFDR) for digitization by use of antenna arrays. Nonlinearities in the analog-to-digital conversion process give rise to spurious signals (harmonics and intermodulation products) that limit the overall SFDR of the digitization process. When the signal of interest arises from a(More)
The paper derives Cramer-Rao lower bounds (CRLBs) for airborne acoustic source tracking estimates using an array of hydrophones. The paper considers both bearing and Doppler frequency measurements in a two layer (air-sea) acoustic environment with unknown source frequency. Comparison of the CRLBs for known/unknown source frequencies is given; the CRLB for(More)