Abstract: A Luneberg lens has a plurality of feeds arranged to send and receive signals to and from a plurality of satellites. The lens is spherical and is fixedly supported on a support mount. Also supported on this mount are a plurality of arcuate positioner tracks which form arcs parallel to the surface of the lens. Each of the feeds is mounted on a separate one of these tracks. The tracks are supported on the mount for separate pivotal motion along separate paths equidistant from the surface of the lens about a “y” axis relative to the lens. A motor is coupled to the drive of each of the tracks to pivotally drive its associated track in response to control signals. The feeds are mounted on the tracks for motion in paths about an “x” axis relative to the lens, such paths being equidistant from the surface of such lens. A motor drives each of the feeds in response to control signals along separate paths parallel to the lens surface.

Abstract: An antenna dish for reflecting signals for a first antenna operating in a first frequency band is mounted in proximity to a second antenna operating in a second frequency band separated from the first band. With the two antennas in certain relative orientations, the dish is partially or totally in the receiving and transmitting path of the second antenna. The dish is modified so that signals in the first frequency band can effectively pass through the dish. This end result is achieved by placing conductive antenna elements over the entire reflecting surface, these elements being dimensioned to efficiently radiate and receive signals in the first frequency band, thereby permitting such signals to effectively pass through the reflector dish.

Abstract: An optical reflector antenna utilizes a subreflector that is offset from the optical axis of the antenna and that revolves about the optical axis to scan the beam from the antenna in a circular path about the axis of the antenna to facilitate the search for and acquisition of a satellite for subsequent tracking and communications. The subreflector is mounted on a rotatable shaft that is aligned with the optical axis of the antenna. When the shaft is not being rotated, one or more springs hold the subreflector in a fixed position aligned with the optical axis of the antenna to facilitate tracking and communications. When the shaft is rotated, rotational forces cause the subreflector to shift to and remain at a position that is offset from the optical axis and the rotation of the shaft causes the offset subreflector to revolve about the optical axis of the antenna, thus scanning the beam from the antenna to facilitate the search for and and the acquisition of the satellite.

Abstract: An antenna feed system provides reception of both circularly polarized signals and linearly polarized signals. An antenna is employed which is dual-circularly polarized and circularly polarized signals received thereby are separated into right and left hand components which are placed in phase quadrature relationship by means of a 90 degree hybrid coupler. Signals received by the antenna which have dual-orthogonal linear polarization are also separated into left and right hand components in quadrature relationship by means of a 90 degree hybrid coupler. A programmable phase shifter is utilized to set the orientation of the linearly polarized reception vector. A fixed delay line and an attenuator are provided for use in balancing the amplitude and phase of the right and left hand components of the linearly polarized signals.

Abstract: A device for driving a stepper motor in variable sized micro-steps in response to slew rate commands. The device integrates the slew rate commands, calculates the currents to be supplied to the windings of the stepper motor and supplies these currents to the stepper motor. The device utilizes an update frequency for the integration, calculation and supply of currents to the stepper motor that is higher than the frequencies of the predominant resonances of whatever system is being driven by the stepper motor. As a consequence, the size of each micro-step executed by the stepper motor in response to slew rate commands is larger for high slew rates and smaller for low slew rates.

Abstract: An array of hemispherical dielectric lenses antenna on a ground plane for focusing radiation from an array of point sources, each point source being located adjacent to its respective hemispherical lens. Dual polarization point sources provide dual orthogonally polarized radiation patterns, including right and left hand circularly polarized radiation patterns. The entire antenna and ground plane may be rotated and the array of point sources may be moved relative to the hemispherical lenses so as to scan the antenna beam over a hemisphere.

Abstract: A semi-cylindrical dielectric lens antenna on a ground plane for focusing radiation from a line source adjacent to the semi-cylinder. Grooves in the surface of the ground plane modify the polarization of the electromagnetic radiation reflected by the ground plane thus allowing conversion of radiation from linear to circular polarization and vice versa. Selectable line sources may be used to provide both right and left hand circularly polarized radiation. The entire antenna and ground plane may be rotated and the line source may be moved relative to the dielectric lens so as to scan the antenna beam over a hemisphere.

Abstract: An antenna having an omnidirectional pattern in azimuth and coverage throughout a hemisphere. The radiating elements are four half-loops mounted on a ground plane. Each half-loop is approximately one-half wavelength in length with one end grounded to the ground plane and the other end fed in opposition to the ground plane. The image produced by the ground plane of each half-loop, together with the actual half-loops give the effect of a set of four complete loops, each of which complete loops is approximately one wavelength in circumference. The elements are nominally located in planes normal to the ground plane that pass through a central point in the ground plane. The planes of the elements are oriented nominally at 90 degree intervals about a central point and the centers of the elements are offset from the central point of the ground plane by approximately one-quarter wavelength. The combination of elements produces an omnidirection radiation pattern in azimuth.

Abstract: The invention is a state machine for the detection of a pre-specified pattern of m bits in a stream of bits where the stream of bits is examined in steps, each successive step consisting of the examination of the next successive set of n bits in the stream of bits. The state machine is mechanized by a look-up table. The current set of n bits is combined with a state number representing the current state of the machine to obtain an address for entry into the look-up table. The state number stored in the table at that address is the new state number representing the new state of the machine after the examination of the current set of n bits in the stream. The new state number is then combined with the next successive set of n bits to obtain the next new state number from the table. Thus each new state number becomes the current state number for combination with the next set of n bits to form the address for entry into the table.