Abstract: A system and method using a Costas loop to effect accelerated convergence with minimal system complexity. The system comprises an in-phase-limiter and a quadrature-phase limiter, operatively coupled to an EXCLUSIVE-OR gate, for exclusively-ORing an in-phase-sign signal and a quadrature-phase-sign signal to output a first error signal, responsive to the signals having same signs, or a second error signal, responsive to the signals having different signs. An AGC circuit, operatively coupled to an output of the EXCLUSIVE-OR gate, increases and decreases a voltage level of an AGC signal responsive to two consecutive first or second error signals and consecutive dissimilar error signals, respectively. A voltage-controlled oscillator, operatively coupled to an output of the AGC circuit and responsive to the increased or decreased voltage level, changes the frequency of a voltage-controlled-oscillator output signal.

Abstract: A phased array spread spectrum system for maximizing signal strength of a spread-spectrum signal with multipath through the use of receiving means, delaying means, combining means, despreading means, generating means, storing means and comparing means. The receiving means receives a plurality of spread-spectrum signals and a plurality of phased versions of the plurality of spread-spectrum signals. The delaying means delays the received plurality of spread-spectrum signals with respect to the plurality of phased versions of the plurality of spread-spectrum signals by a plurality of delays. The combining means combines the delayed spread-spectrum signals and the plurality of phased versions of the plurality of spread-spectrum signals as a plurality of combined signals. The despreading means despreads the plurality of combined signals as a plurality of despread signals. The generating means generates a plurality of magnitude values from the plurality of despread signals.

Abstract: An apparatus for adaptive-power control of a spread-spectrum transmitter of a mobile station operating in a cellular-communications network using spread-spectrum modulation. A base station transmits a first spread-spectrum signal. A mobile station has an automatic-gain-control circuit for generating an AGC-output signal, from a received signal. The received signal includes the first spread-spectrum signal and an interfering signal.

Abstract: A spread-spectrum-matched-filter apparatus including a code generator, an in-phase-programmable-matched filter, a quadrature-phase-programmable-matched filter, an in-phase-frame-matched filter, a quadrature-phase-frame-matched filter, and a controller. The code generator generates replicas of a pilot-chip-sequence signal and a data-chip-sequence signal, which are used to set the programmable-impulse responses of the in-phase-programmable-matched filter and the quadrature-phase-programmable-matched filter. The programmable-impulse responses are alternately changed between that of the pilot-chip-sequence signal and the data-chip-sequence signal so that the in-phase-programmable-matched filter and the quadrature-phase-programmable-matched filter alternately detect the pilot-spread-spectrum channel and the data-spread-spectrum channel embedded in a received spread-spectrum signal, respectively.

Abstract: A cathode ray tube suitable for use as a visual display includes two or more electron guns. The beams from the electron guns are aligned vertically so that a single horizontal scan of the guns produces two rows of pixels on the front face of the tube. This allows twice as much data to be painted on the display screen without increasing the scan rate of the electron guns. Each of the guns may be a single beam gun, for monochrome displays, or each may be a triple-element gun for RGB displays.

Abstract: A network controller card having a processor, memory and program logic. The program logic can be used as communications circuits and as testing circuits. A reconfigure signal from a workstation remotely located from the network controller card initiates the processor to change the program logic from communications circuits to testing circuits and vice versa.

Abstract: A conference calling spread-spectrum communications system and method using a plurality of spread-spectrum units, any one of which may serve as the base station and where the base station may be changed from one spread-spectrum unit to another upon command. Each spread-spectrum unit includes a base subunit, a remote subunit, and a command subunit. An operator may initiate from the command subunit of a particular spread-spectrum unit, a command signal to activate the base subunit of the particular spread-spectrum unit. Upon initiating the command signal, the particular spread-spectrum unit is activated as the base station and the command signal is broadcast to the remaining plurality of spread-spectrum units.

Abstract: A method for imaging, broadcasting and viewing images, simultaneously three-dimensional and two-dimensional, of object space. The invention comprises a camera device, a remote viewing device, a drive signal generator, a transmitter, and a pair of viewing glasses. The camera device includes a single imaging lens having a bifurcated, dual-aperture light valve, and a single image space for receiving and overlaying a plurality of left-eye images and a plurality of right-eye images at a field rate driven by the drive signal. The transmitter transmits the images, as an image signal, and the drive signal. The remote viewing device receives the image signal and reconverts the image signal to the plurality of left-eye images and the plurality of right-eye images. The pair of viewing glasses receives the drive signal and in response thereto, opens and closes the left and right viewing-light valves, synchronized with the field rate, for viewing the left and right eye images, respectively.

Abstract: A video processor, having an input and an output, for compensating for accumulated phase and amplitude errors encountered during transmission of a video signal over a communications channel. The video processor includes a high-pass filter and amplifier, coupled to the input; a post-correction-phase-and-gain restorer; a wide-band-video-delay line coupled to the input; a pre-correction-comb-equalizer restorer; and a combining network, coupled to the output. The high-pass filter has a bandwidth characteristic which is approximately inverse to a low-pass characteristic encountered by the video signal during its transmission over the communications channel. The high-pass filter takes the video signal and outputs a filtered-video signal. The amplifier associated with the high-pass filter inverts the filtered-video signal. The post-correction-phase-and-gain restorer adjusts the inverted-filtered-video signal to generate a restored-video signal.

Abstract: A backscatter type non-invasive blood oximeter utilizes a coherent, polarized and tuneable monochromatic light source to measure parameters related to blood oxygen content. A microprocessor calculates information related to blood oxygen content from the sensed information and a display system displays the blood oxygen content.

Abstract: A method for demodulating a received spread-spectrum signal using a minimum-shift-keyed (MSK) receiver. Using the method, an in-phase-component signal and a quadrature-phase-component signal are generated from a received spread-spectrum signal. The in-phase-component signal and the quadrature-phase-component signal are then processed and combined in such a way as to estimate data of the received-spread-spectrum signal.

Abstract: A spread spectrum CDMA communications system for communicating data and/or digitized voice between a plurality of users to a plurality of PCN units. The spread spectrum communications system is located within a same geographical region as occupied by an existing FDMA, proposed TDMA or any other mobile cellular system. The spread spectrum CDMA communications system includes a plurality of PCN-base stations and a plurality of PCN units. A PCN-base station has a comb filter for notch filtering predetermined channels of the mobile cellular system, a device for converting the format of the data into a form suitable for communicating over radio waves, a spread spectrum modulator for spread spectrum processing the data, and a transmitter for transmitting the spread spectrum processed converted data from the PCN-base station to a PCN unit. The PCN-base station also has an antenna, and spread spectrum detectors for recovering data communicated from the PCN units.

Abstract: A system and method for adaptive power control of a spread spectrum transmitter of a mobile unit operating in a cellular-communications network having a plurality of mobile units in communication with a base station. In response to a received signal from the mobile unit, the received signal having a first spread-spectrum signal and an interfering signal, an automatic gain control (AGC) circuit within the base station generates an AGC-output signal which is despread by base despreader and then processed as a received-power level. The received power level is then compared to a threshold level to generate a power command signal. The power command signal is transmitted to the mobile station as a second spread-spectrum signal. The mobile station despreader despreads the second spread-spectrum signal as a power adjust signal and, responsive to the power adjust signal, increases or decreases the power level of the first spread spectrum signal.

Abstract: A variable bandwidth filter device for use with a spread-spectrum transmitter including a chipping sequence generator, spread-spectrum processing means, an impulse generator, and a filter. The chipping-sequence generator generates a chipping sequence signal having a chipping-sequence-signal bandwidth. Using the chipping sequence signal, the spread-spectrum processing means processes a data signal to generate a spread-data signal having a spread bandwidth greater than the chipping-sequence-signal bandwidth. In response to each chip in the spread-data signal, the impulse generator generates an impulse signal. The filter filters the spectrum of each impulse signal with a bandpass equal to the spread bandwidth. The invention also comprises a method for generating a spread-spectrum signal using a chipping sequence having a rate less than the spread bandwidth.

Abstract: A spread-spectrum code division multiple access interference canceler system and method for reducing interference in a spread-spectrum CDMA receiver having N chip-code channels, with each of the N channels identified by a distinct chip-code signal. The interference canceler system comprises a plurality of interference cancelers, each having chip-code generators, delay devices, correlators, spread-spectrum-processing circuits, and subtracting means. Using a plurality of chip-code signals, the correlators despread the spread-spectrum CDMA signal as a plurality of despread signals, respectively. The spread-spectrum-processing circuits use a timed version of the plurality of chip-code signals, generated by the delay devices, for spread-spectrum processing the plurality of despread signals, respectively, with a timed chip-code-signal corresponding to a respective despread signal.

Abstract: A wide area communications network communicating data from a plurality of network service modules through a plurality of remote cell nodes and intermediate data terminals to a central data terminal. The wide area communications network collects network data generated by a plurality of physical devices such as gas, water or electricity meters, located within a geographical area. The wide area communications network is a layered network having a hierarchical communications topology. The central data terminal controls network operation. Intelligence exists at all layers of the network, thereby easing the workload of the central data terminal. The intelligence attributed to each module is a function of the application of that module.

Abstract: A method using a central computer and a work station for managing inventory. To dispense inventory to consumers, a system user is issued a card imprinted with a personal user bar code. This user bar code is read into the computer and subsequently verified through the entry of individual user access data to ensure the user is authorized. To issue an item to a consumer, the user must next identify through an input means the particular consumer to whom the item is to be issued. The item to be issued is imprinted with an item bar code. After identifying the consumer, the item bar code is read into the work station and converted to issued-item data. The issued-item data is communicated from the work station to the central computer, where the issued item is decremented from inventory data. The central computer then determines whether each issued item is chargeable to the particular consumer.

Abstract: A system and method for adaptive-power control of a spread-spectrum transmitter of a mobile station operating in a cellular-communications network using spread-spectrum modulation. A mobile station transmits a first spread-spectrum signal. A base station has an automatic-gain-control circuit for generating an AGC-output signal, from a received signal. The received signal includes the first spread-spectrum signal and an interfering signal. The base station also has a correlator for despreading the AGC-output signal, a power-measurement circuit responsive to processing the received signal with the despread AGC-output signal for generating a received-power level, a comparator coupled to the power-measurement circuit for generating a comparison signal by comparing the received-power level to a threshold level, a transmitter for transmitting a second spread-spectrum signal, and an antenna.

Abstract: A multicarrier direct sequence spread spectrum system and method. A maximal combiner is employed at the receiver for maximizing signal-to-noise ratio out of the receiver. The multicarrier system provides robustness against multipath fading, and narrowband interference suppression. The multicarrier system is suitable for a CDMA overlay scheme for PCN.

Abstract: A spread-spectrum transmitter and receiver using code division multiple access with time division multiple access technology for spread-spectrum communications. At a base station, a spread-spectrum transmitter includes a multiplexer for time multiplexing a synchronization-code signal and a plurality of data signals, which may be encoded as a plurality-encoded data signals, to generate a time-multiplexed signal. A chip code generator generates a chip-code signal which is modulo added with the time-multiplexed signal by an EXCLUSIVE-OR gate to generate a spread-spectrum-time-multiplexed signal. A transmitter transmits the spread-spectrum-time-multiplexed signal over a communications channel. A spread-spectrum receiver at the base station processes a plurality of spread-spectrum signals, received from a plurality of remote units in as time division sequence of spread-spectrum signals, using a despreader circuit to generate a time-division signal.