A system and method are described that use impulse radio technology to enhance the capabilities of a robot. In one embodiment, a system, a robot and a method are provided that use the communication capabilities of impulse radio technology to help a control station better control the actions of the robot. In another embodiment, a system, a robot and a method are provided that use the communication, position and/or radar capabilities of impulse radio technology to help a control station better control the actions of a robot in order to, for example, monitor and control the environment within a building.

Method and system for controlling a robot

A method for determining the geolocation of an emitter using sensors located at a single or multiple platforms is disclosed. Generally, the method includes the steps of receiving a first measurement set relative to a first emitter, the first measurement set including angle of arrival, time difference of arrival and/or terrain height/altitude measurements, receiving a first location guess or estimate for the first emitter, and determining at least a second location estimate using at least one of a batch least squares analysis and a Kalman filter analysis.

Multi-platform geolocation method and system

Quadrature phase discriminators, the core of wideband instantaneous frequency measurement (IFM) receivers and multiple base-line interferometry for accurate direction finding (DF), were invented in 1957, by S.J. Robinson of Mullard Research Laboratories (MRL). Digital instantaneous frequency measurement (DIFM) receivers have been universally used operationally for wideband monitoring of radar environments in naval, airborne and ground-based electronic support measures (ESM) systems all over the world for over 50 years. Their importance is such that many countries have developed their own IFM manufacturing capability with just minor architectural changes to the original design. This study describes the invention sequence, the development history, IFM design and performance principles, its general use and limitations in modern electronic warfare (EW) systems and ends with a projection for the future.

Fifty years of instantaneous frequency measurement

A system and method for determining angular offset of an impulse radio transmitter using an impulse radio receiver coupled to two antennae. The antennae are separated by some known distance, and, in one embodiment, one antennae is coupled to the radio with cable delay. Impulse signals from the antennae are measured to determine the time difference of arrival of one such signal received by one antenna compared to that of the other antenna. Time differential is measured by autocorrelation of the entire impulse radio scan period, by detecting the leading edges of both incoming signals or various combinations of these methods. Using a tracking receiver, the pulses may be continuously tracked thus providing real time position information.

Impulse radio receiver and method for finding angular offset of an impulse radio transmitter

A precision direction finding system for making precision angle of arrival estimates for a signal received through two antenna elements separated in space. Phase interferometry is used to determine a precise angle of arrival, with multiple ambiguities due to the periodic nature of the phase difference related to geometric angle. The interferometric ambiguities are resolved using the time difference of arrival (TDOA) of the signal at the two antenna elements. TDOA is measured using leading edge envelope detection for simple pulsed signals, and predetection correlation for phase and frequency modulated signals.

Phase and time-difference precision direction finding system

The method provides the capability to estimate the angle-of-arrival (AOA) of radar pulses with respect to a ground or airborne based platform. It utilizes a spectral estimation technique which extracts the periodic properties of radar signals whose time-of-arrivals (TOAs) have been tagged by an Electronic Warfare receiver. The method can be used in a multiple signal environment and can separate and individually measure AOA of emitters that are spatially very close but have incommensurate Pulse Repetition Intervals (PRIs).

Angle-of-arrival measurement via spectral estimation of radar time-of-arrival periodicities

A technique covered by patent applicaton S.N. 07/672,309 divides power of an input signal to two A/D converters. A processor receives the outputs of the two A/D converters. The input signal is subjected to a known delay τ for one of the converters, and both original and delayed signals are sampled simultaneously. Both sampled signals are Fourier transformed and the phase and amplitudes calculated, using the expressions: φ(f)=tan.sup.-1 [I(f)/R(f)] A(f)=[R.sup.2 (f)+I.sup.2 (f)].sup.1/2 where R(f) and I(f) are respectively the real and imaginary parts of the frequency transform. The phase difference between the original and delayed signals is calculated and an approximation to the true frequency for each peak observed in the amplitude spectrum is estimated using the expression φ=2πfτ where τ is the delay. Herein the input signal is down-converted into two parallel paths with frequencies which differ by f s /4 where f s is the sampling rate. The alias boundaries are at multiples of f s /2. The output signals are divided again into two paths to form the delayed and undelayed paths. The digitized data will be processed as in the phase shifted sampling approach above. Since the four digitizers are operated at a synchronized speed, the outputs will be processed at one single clock rate.

Frequency measurement receiver with bandwidth improvement through synchronized phase shifted sampling

Embodiments include active protection systems and methods for an aerial platform. An onboard system includes one or more radar modules, detects aerial vehicles within a threat range of the aerial platform, and determines if any of the plurality of aerial vehicles are an aerial threat. The onboard system also determines an intercept vector to the aerial threat, communicates the intercept vector to an eject vehicle, and causes the eject vehicle to be ejected from the aerial platform to intercept the aerial threat. The eject vehicle includes a rocket motor to accelerate the eject vehicle along an intercept vector, alignment thrusters to rotate a longitudinal axis of the eject vehicle to substantially align with the intercept vector, and divert thrusters to divert the eject vehicle in a direction substantially perpendicular to the intercept vector. The eject vehicle activates at least one of the alignment thrusters responsive to the intercept vector.

Methods and apparatuses for active protection from aerial threats

Disclosed is a method to extract the periodic properties (or Pulse Repetition Intervals (PRIs)) of radar signals whose time-of-arrival at an airborne platform have been time tagged by an Electronic Warfare (EW) receiver. The PRIs are determined using a modified Discrete Fourier Transform (DFT) written as ##EQU1## where k represents the frequency components, the Ti are the individual Time-Of-Arrival (TOA) data values and N is the last TOA value collected. Disclosed are three possible methods of reducing the number of computations involved with the modification of the Discrete Fourier Transform (DFT) equation to facilitate its use with Radar Time-Of-Arrival (TOA) to extract periodic properties of radar signals. This is particularly applicable to radar pulse trains which are interleaved in time and where each individual pulse train may be staggered or jittered in time so that a time domain deinterleaving scheme must be employed. A spectral estimator can be computed by taking the modulus of the DFT of the time series data and extending the periodogram estimator by making a slight modification of the DFT equation.

Spectral estimation of radar time-of-arrival periodicities

Embodiments include engagement management systems and methods for managing engagement with aerial threats. Such systems include radar modules and detect aerial threats within a threat range of a base location. The systems also track intercept vehicles and control flight paths and detonation capabilities of the intercept vehicles. The systems are capable of communication between multiple engagement management systems and coordinated control of multiple intercept vehicles.

David L. Sharpin

Papers

Angle-of-arrival measurement via spectral estimation of radar time-of-arrival periodicities

Frequency measurement receiver with bandwidth improvement through synchronized phase shifted sampling

Methods and apparatuses for active protection from aerial threats

Spectral estimation of radar time-of-arrival periodicities

Methods and appratuses for engagement management of arial threats