Abstract: A DTV pilot tone is detected in a noisy environment by computing a power average of Fast Fourier Transform (FFT) output spectra of a received signal, finding a power peak in the averaged outputs, computing an adjustment parameter to center the power peak in a Discrete Fourier Transform bin of the averaged output spectra, applying the adjustment parameter to adjust the received signal, computing a coherent average of FFT output spectra of the adjusted signal, and, testing a power spectrum of the coherent average for the presence of the DTV pilot tone.

Abstract: A DTV pilot tone is detected in a noisy environment by computing a power average of Fast Fourier Transform (FFT) output spectra of a received signal, finding a power peak in the averaged outputs, computing an adjustment parameter to center the power peak in a Discrete Fourier Transform bin of the averaged output spectra, applying the adjustment parameter to adjust the received signal, computing a coherent average of FFT output spectra of the adjusted signal, and, testing a power spectrum of the coherent average for the presence of the DTV pilot tone.

Abstract: A high-accuracy method for the geolocation, without the collaboration of the network, of outdoor mobile emitters of a CDMA cellular system, based on the ability to distinguishing between line-of-sight and reflected signals. The method employs time-of-flight and angle-of-arrival information in order to determine whether a signal received by each of two or more interceptors situated at different locations is line-of-sight or reflected. Time-of-flight information is obtained with the aid of the reverse link of a mobile of interest. At those instances in time when the signal received at two or more interceptors is line-of-sight, the location of the mobile can be accurately determined using conventional direction-finding techniques. Since the signal received by an interceptor from a mobile may be very weak, adaptive threshold digital signal processing techniques may be employed to control the probability of detection and the probability of false alarms.

Abstract: A system and a method of locating a co-operative transceiver in an indoor location by setting up multiple transmitting beacons outside of a building in which the transceiver is located. Information at the transceiver, such as time-of-arrival (TOA) or time-difference-of-arrival (TDOA) of the first-to-arrive signals originating from the external beacons, is relayed back to a processing centre. The angle-of-transmission (AOT) is then determined for the first-to-arrive signals, the only ones with a potential for line-of-sight signals, as well as any arriving reflected signals. Synthetic Doppler, by revolving the transmitting antenna, is used to distinguish between a line-of-sight received signal in order to accurately determine the location of the transceiver.

Abstract: A loop antenna which is electrically small relative to a wavelength of a signal which it is designed to receive. The antenna is an electrically small, low profile, band switchable antenna which can be mounted on a metallic surface such as a truck or railway car rooftop and can be used to communicate with earth satellites. The antenna is polarized such that the plane containing the electric field is horizontal. Alternatively, the antenna can receive circularly polarized signals.

Abstract: An antenna array is disclosed wherein radiators are parasitically coupled to each other, forming an efficient feed network. Parasitic coupling of patches is arranged so that some patches are fed by a plurality of other patches which are parasitically coupled thereto. The resulting array is low profile and high gain. By positioning patches on different layers with different dimensions, a broadband design for the antenna array is achieved.

Abstract: A continuous wave, phase measurement system which provides at least an order of magnitude improvement in accuracy over modulated carrier systems is disclosed for the determination of the thicknesses of layered targets consisting of a known number of dielectric layers, each of a known maximum thickness. This system uses related frequencies such as the fundamental and its harmonics to establish a multi-harmonic coherence relationship whereby a homodyne phase reference between harmonics can be conserved and information extracted from just the received and not the transmitted signals. Consequently doppler effects due to motion between the target and the apparatus, as well as severe local oscillator stability and drift limitations are avoided, and thus this system can measure remote target parameters by interferometric techniques without the distance being a constraint.