Abstract: A phase/phase/frequency-scan radar apparatus having multiple-beam search and single-beam track capabilities, using a single array antenna employing a novel combination of phase/phase scan in two dimensions together with frequency-scan. Generally, the additional frequency scan capability need be used in one dimension only, preferably azimuth, but the concept could readily be extended to two-dimensional add-on frequency scan if desired.

Abstract: A radar system is disclosed which includes a transmitter which produces a long coded radar pulse. The return of the long coded radar pulse is compressed by a long pulse compression filter to produce a short coded pulse and the short coded pulse is compressed by a short pulse compression filter to produce a return pulse for processing by an existing processor designed to process return coded pulses of a particular format. The long pulse transmitter can also transmit a short coded precursor pulse, to improve radar range coverage, along with the long coded pulse by the provision of a switching bypass device which routes the short coded pulse return signal around the long pulse compression filter.

Abstract: Polystatic radar system and method for operating at relatively low power for a given coverage. The illumination power density of the transmit pattern is continuously varied as a function of the range to the receiver from each point within the receive beam coverage.

Abstract: In a surveillance radar, a process is disclosed which can determine the angular positions of multiple jammers with the use of a monopulse agile beam antenna. It involves collecting and processing jammer data received via a monopulse antenna, in order to determine jammer location, and to resolve two jammers within the main beam when present. A feature is the use of the ratio of the imaginary and real parts of the difference/sum ratio as a discriminant to select a subset of multiple measurement data points, from which the individual jammer angular locations can be determined, when two jammers are present, by averaging upper and lower percentiles of the real difference/sum ratio data points of that subset.

Abstract: An azimuth-stacked radar method and apparatus of the type typically used for surveillance employs a mechanically-rotating antenna comprising horizontal end-fed rows of antenna radiating elements with phase shifter control on each row together with a monopulse elevation manifold to generate an elevation sum and difference beam pair. Additionally, this radar employs a waveform comprising multiple subpulses at different frequencies with sufficient separation between the subpulses at each frequency to spread them in azimuth to form a beam cluster and employs mechanical antenna rotation and phase-responsive elevation scanning. The scanning is accomplished in a way that will permit advantageous avoidance of ground clutter and other uninteresting radar reflectors.

Abstract: A radar search detection apparatus having a monopulse antenna to receive sum and difference beam signals which are applied to separate target detection channels to detect and identify target returns.

Abstract: A signal processor for radar systems having phased array antenna structures. The processor determines the angle of arrival of the signal from a discrete energy source. The separate elements or output ports of the antenna structure are sampled to form a matrix of signal values. These values are converted into polynomial expressions consistent with one of the spectral estimating methods of maximum entropy, maximum likelihood, and thermal noise. The roots of the polynomial expressions are found and compared to the distance of the unit circle in a pole-zero diagram. Roots sufficiently close to the unit circle are selected as representative of the source signal peaks and the angular directions to such sources are determined by the corresponding angular location of the selected roots in the pole-zero diagram.

Abstract: A lifting and towing unit mountable on a fifth wheel of a towing vehicle has an anchoring frame assembly with a king pin for coupling to the towing vehicle fifth wheel and a lifting frame assembly adapted to support a portion of a mobile load and to be releasably attached thereto and to the anchoring frame assembly in a fixed relation thereto. The unit also includes an arrangement in the form of a four-bar linkage interconnecting and mounting the lifting frame assembly rearwardly of and to the anchoring frame assembly for pivotal movement relative to the frame of the towing vehicle between lowered and raised positions.

Abstract: A continuous wave radar system arrangement for improving the dynamic range of the radar receiver. The transmitted carrier signal is frequency modulated by a periodic sawtooth waveform causing a predetermined peak frequency shift. The radar receiver includes a plurality of separate receiving channels each selective to a small portion of the transmitted bandwidth. As the sawtooth modulation causes the carrier signal to sweep in frequency, the received leakage and clutter signals in the selective receiving channels are blocked momentarily and individually in each channel. The outputs of the separate receiving channels are combined to form a composite signal of the echo returns. Gaussian filters with quadratic phase compensation are used to provide the selectivity of the receiving channels.

Abstract: A recovery unit for use by one truck tractor in towing another disabled truck tractor has an anchoring frame assembly with a king pin for coupling to a fifth wheel of the towing tractor and an attaching frame assembly with a king pin for coupling to a fifth wheel of the disabled tractor. The attaching frame assembly is mounted for pivotal movement relative to the anchoring frame assembly between stored and extended conditions. Actuating cylinders and an auxiliary frame assembly are selectively operable to pivot the attaching frame assembly relative to the anchoring frame assembly between the stored and extended conditions and to pivot the attaching frame assembly to and from an erected position relative to the anchoring frame assembly once the attaching frame assembly has been first moved to its extended condition and coupled to the fifth wheel of the disabled tractor.

Abstract: A hitch uncouple detecting and signaling apparatus, being applied to a trailer hitch ball member, includes a plunger rod reciprocally mounted vertically through the ball member. The rod is longer than the ball member, allowing the rod to extend either above or below opposite upper and lower ends of the ball member. The rod is composed of electrically nonconductive material capable of being trimmed to a length which will exceed the ball member height at least by a desired amount. An electrical circuit adapted for connection to a source of electrical power includes an operator signaling device and a pair of contacts. One contact is carried by a lower end of the rod and the other contact is defined on the lower end of the ball member, which preferably is composed of electrically conductive material.

Abstract: In a radar operating in a moving target indication (MTI) mode with frequency diversity by transmitting N+1 pulse bursts and receiving echo signalling therefrom, a radar channel is included for doppler processing the received N+1 pulse echo signal bursts. Each pulse of the same burst envelopes a fixed carrier frequency. The radar is operative to change the transmitted carrier frequency from one pulse burst to another. The radar channel comprises an MTI filter operative as two different orthogonal MTI filters, each having a frequency response similar to an N-pulse MTI filter, to process functionally in parallel a received N+1 pulse echo signal burst to generate a filter signal from each functional filter. Also included is apparatus for combining the two filter signals non-coherently to generate a composite signal corresponding to the N+1 pulse echo signal burst for target detection. The radar channel is operative to process N+1 pulse bursts with either fixed or variable interpulse periods.

Abstract: The striking cap of a badminton shuttlecock is formed as a hollow, truncated sphere having a hole in its outer end and having several holes through its spherical wall to reduce the influence of wind on the flight path of the shuttlecock. The shape of the striking cap also enables the shuttlecock to be better used with damaged racquets without sticking in the torn webbing thereof.

Abstract: The machine includes a power-reciprocated blade adapted to be driven by a conventional electric drill and adapted to strip cemented carpet away from a floor. The blade and the handle grips of the machine are adapted to be shifted to laterally compact storage positions to facilitate carrying and storage of the machine.

Abstract: A low PRF pulse doppler radar system utilizing a VIP digital filter bank signal processor to suppress echoes from terrain, rain, and chaff, and pass echoes from aircraft moving at higher speeds is disclosed.Each of a plurality of VIP filters individually provides high attenuation to undesired signals over designated frequency bands, the width of which are a large fraction of 1/T.sub.av where T.sub.av is the average interpulse period. Little or no attenuation of desired signals having doppler frequencies greater than 1/T.sub.av occurs. The outputs of the plurality of filters are desensitized to prevent false alarm from clutter, and the presence of a desired radar pulse echo is determined by a comparison with a threshold level.

Abstract: An automatic phase and gain balance controller is incorporated in a typical baseband processor of a MTI radar system employing doppler processing techniques to effect balancing adjustments in the in-phase (I) and quadrature (Q) signal generation channels for substantially eliminating spurious image frequency component formations which may result from any unbalance therein. More specifically, the automatic controller provides two substantially non-interactive servo control loops to maintain balance between the I and Q signal generation channels by performing balancing adjustments on two adjustment parameters, namely phase and amplitude. Phase and amplitude imbalance errors between the I and Q channel are obtained in response to a pilot signal which is injected into the baseband processor of the MTI radar receiver, perferably during the dead times of the interpulse periods of pulsed reception.

Abstract: Apparatus for use in a sanding and shaping or other machine comprised of a plurality of individually mounted feeding and hold down members adapted to engage and hold a work piece against a table and against a guiding fence as the work piece is fed through the machine to keep the work piece from turning or binding in the machine.

Abstract: A cylindrical rotary cutting head rotatable about a longitudinal axis having a plurality of helical slots in which a plurality of bits carrying cutting edges are retained in the lateral direction by means of set screws which bear against a "V" groove in an inclined face of the bit and in the vertical direction by plurality of cooperating serrations on an opposite face of the bit and in one slot wall.