Abstract: A method and apparatus for a demodulator circuit in a communication system is described. The invention relates to a demodulator circuit in a communication system using a multi-carrier modulation scheme. The demodulator makes efficient use of channel state information for respective carriers in the multi-carrier modulation to de-map the received data. An efficient method of calculating channel state information is also disclosed.

Abstract: A method and apparatus for receiving radio frequency signals in a communication system is described. The inventive method and apparatus utilizes an inventive receiver circuit that downconverts an input signal so that interference components of the input signal can be easily removed at baseband. Specifically, the inventive receiver circuit operates by sub-sampling a first intermediate frequency signal in such a way that an unwanted signal is not aliased into a wanted signal, and can therefore be filtered therefrom after sub-sampling. Thus, the present invention allows the use of a relatively simple tuner, with a single downconversion stage, without imposing excessive requirements on the filtering in the tuner.

Abstract: An apparatus for limiting body motion as a patient lies down includes a pad shaped to prevent the patient from rolling over the pad. The pad is shaped so that it projects outwardly 3 inches or more from the patient when attached to the human body. The base of the pad contacts the patient's skin or sleep clothes. The pad has sidewalls which make an angle of greater than approximately 35° degrees with respect to the base. A removable, washable covering is placed on the pad. An attachment mechanism associated with the pad and the covering attach the pad and cover to the human body. The attachment mechanism can be a hook-and-loop fastener, a sports bra type device, a series of straps, a series of snaps, or a series of hooks. In each instance, the pad can be positioned at several positions on the body, including positions to the right or left of the patient's medial plane. More than one pad can also be used to limit the body motion of a patient.

Abstract: The invention provides a single chip implementation of a digital receiver for multicarrier signals that are transmitted by orthogonal frequency division multiplexing. Improved channel estimation and correction circuitry are provided. The receiver has highly accurate sampling rate control and frequency control circuitry. BCH decoding of tps data carriers is achieved with minimal resources with an arrangement that includes a small Galois field multiplier. An improved FFT window synchronization circuit is coupled to the resampling circuit for locating the boundary of the guard interval transmitted with the active frame of the signal. A real-time pipelined FFT processor is operationally associated with the FFT window synchronization circuit and operates with reduced memory requirements.

Abstract: A method and apparatus are disclosed for determining the boundaries of guard intervals of data symbols being received in a coded orthogonal frequency division multiplexed signal. Temporal samples separated by an interval of an active interval of a data symbol are associated in pairs, and difference signals obtained. The dispersion of a first comparison block of difference signals is determined, and compared to the dispersion of a second comparison block of difference signals, the second comparison block being displaced from the first comparison block by n samples. An F ratio is calculated for the dispersions of the two blocks. F ratios are iterated in a succession of comparison blocks, and a signal representing the F ratios subjected to peak detection. The peaks represent the boundaries of the symbol's guard interval. This information is utilized in synchronizing an FFT window for subsequent signal reconstruction.

Abstract: One-piece jaw exerciser/strengthener, custom fit, aligned and located over and about the teeth of the upper or lower jaw including one or more resilient substantially tubular members on an exterior surface, which resiliently interface with teeth of the upper or lower jaw. The jaw exerciser/strengthener can be custom formed over a dental casting, or can be formed by heating of the device and biting down to cause a conformed fit to the upper or lower jaw teeth and/or gum area.

Abstract: An intraoral orthopedic appliance with adjustment apparatus and method of manufacture adjustably attaches an appliance upper dental part and lower dental part together. One appliance part is arranged to be attached to a patient's upper dental arch and the other to the patient's lower dental arch. The adjustment changes the anterior-posterior relationship of the two parts. The adjustment is provided by a pair of orthodontic screws on buccal segments of opposite sides of the dental arch which connect the two parts together to provide the adjustment. The orthodontic screws are also attached to the lower appliance part such as to provide a limited movement between the two parts. This allows the patient to move the lower jaw a limited amount with respect to the upper jaw.

Abstract: Dental appliances formed using this method provide projections of the appliance itself which provide the necessary gripping forces rather than extraneous wires or other parts. The projections are formed by cutting grooves in casts of the teeth arches which will result in a projection, which will bear against the teeth, when the cast surface is duplicated in plastic. A first embodiment forms upper and lower plastic components, each having projections from the casts using the lost wax technique. These components are joined together in a predetermined relationship using a wax bite registration taken while the patient held his jaw in the predetermined relationship, and a dental articulator. A second method forms the plastic components directly over the casts. In this method the components are joined together, while mounted over the patient's arches, with the patient holding his jaw in the predetermined relationship.