Abstract: A novel and useful acquisition and synchronization mechanism for spread spectrum communication systems whereby a synchronization sequence comprising a plurality of known symbols spaced apart by predefined time delay intervals is transmitted as the start of packet signal. At the transmitter, a synchronization sequence is transmitted at the beginning of each packet. A synchronization sequence is generated which includes a plurality of symbols with predefined time gaps between each of the symbols. Multiple synchronization sequences may be generated wherein each sequence comprises a unique set of time delays or gaps between each of the symbols. Each set of unique time delays or gaps between symbols of a sequence is stored as a synchronization sequence gap template in memory.

Abstract: The invention is an imager assembly for a miniature camera head. The assembly comprises an imaging sensor having conductive leads; an objective lens system placed on top of the sensor; circuitry, mounted beneath the imaging sensor, for driving the sensor and amplifying the electrical signals; and conductive wires electrically linking the internal components of the assembly and for linking the assembly to remote locations. The conductive leads are bent and the circuitry and conductive wires are arranged and mounted such that the dimensions in a plane parallel to the sensor plane of the camera head are approximately equal to or less than the dimensions in the plane of the sensor. The circuitry is capable of delivering signals produced by the imaging sensor for further processing and the components of the imager, except for the imaging surface of the sensor and the objective lens system, are encapsulated by an isolating material.

Abstract: The invention is an imager assembly for a miniature camera head. The assembly comprises an imaging sensor having conductive leads; an objective lens system placed on top of the sensor; circuitry, mounted beneath the imaging sensor, for driving the sensor and amplifying the electrical signals; and conductive wires electrically linking the internal components of the assembly and for linking the assembly to remote locations. The conductive leads are bent and the circuitry and conductive wires are arranged and mounted such that the dimensions in a plane parallel to the sensor plane of the camera head are approximately equal to or less than the dimensions in the plane of the sensor. The circuitry is capable of delivering signals produced by the imaging sensor for further processing and the components of the imager, except for the imaging surface of the sensor and the objective lens system, are encapsulated by an isolating material.

Abstract: A novel robust communications scheme whereby a repetition code at the transmitter and an associated cumulative decoder at the receiver are used to increase the reliability of transmission in a communications system. The robust communications scheme of the present invention is effective to increase the reliability of transmission by repetitively transmitting each data segment a number of times in accordance with a repetition code and subsequently collecting the received energy at the receiver over an accordingly longer period of time. Accumulating the received energy over a longer period of time at the receiver, yields a marked improvement in the signal to noise ratio (SNR) of the receiver.

Abstract: A novel and useful acquisition and synchronization mechanism for spread spectrum communication systems whereby a synchronization sequence comprising a plurality of known symbols spaced apart by predefined time delay intervals is transmitted as the start of packet signal. At the transmitter, a synchronization sequence is transmitted at the beginning of each packet. A synchronization sequence is generated which includes a plurality of symbols with predefined time gaps between each of the symbols. Multiple synchronization sequences may be generated wherein each sequence comprises a unique set of time delays or gaps between each of the symbols. Each set of unique time delays or gaps between symbols of a sequence is stored as a synchronization sequence gap template in memory.

Abstract: A novel and useful acquisition and synchronization mechanism for spread spectrum communication systems whereby a synchronization sequence comprising a plurality of known symbols spaced apart by predefined time delay intervals is transmitted as the start of packet signal. At the receiver, the received signal is correlated against the synchronization sequence using the predefined gaps or time delay intervals inserted between the symbols. The received signal is linearly correlated to generate a correlation peak for each symbol received. The expected position of each correlation peak is calculated and compared to the positions of the correlation peaks received. If the number of matches exceeds a threshold, synchronization is declared.

Abstract: A interleaver/de-interleaver mechanism for reducing the latency of transmitted interleaved codewords. The interleaver/de-interleaver mechanism utilizes a shortened first codeword which functions to offset the interleaving and transmission on subsequent codewords so as to achieve reduced latency depending on the degree of shortening applied. The interleaver/de-interleaver mechanism is particularly useful in power line carrier based systems to reduce the exposure to burst errors by providing interleaving with minimal latency penalty.

Abstract: A novel and useful interleaver/de-interleaver mechanism for reducing the latency of transmitted interleaved codewords. The interleaver/de-interleaver mechanism utilizes a shortened first codeword which functions to offset the interleaving and transmission of subsequent codewords so as to achieve reduced latency depending on the degree of shortening applied. The interleaver/de-interleaver mechanism is particularly useful in power line carrier based systems to reduce the exposure to burst errors by providing interleaving with minimal latency penalty.

Abstract: A novel and useful acquisition and synchronization mechanism for spread spectrum communication systems whereby a synchronization sequence comprising a plurality of known symbols spaced apart by predefined time delay intervals is transmitted as the start of packet signal. At the receiver, the received signal is correlated against the synchronization sequence using the predefined gaps or time delay intervals inserted between the symbols. The received signal is linearly correlated to generate a correlation peak for each symbol received. The expected position of each correlation peak is calculated and compared to the positions of the correlation peaks received. If the number of matches exceeds a threshold, synchronization is declared.

Abstract: A novel and useful windowing mechanism for reducing the out of band harmonics of an output transmit signal. The windowing mechanism functions to smooth the transition between two consecutive transmit waveforms. The mechanism of present invention is particularly useful in communication systems characterized by consecutively transmitted symbols whereby the concatenation of transmitted waveforms causes discontinuities between symbols. The windowing mechanism is operative to reduce the effect of these discontinuities to reduce out of band harmonics of the transmitted output signal. The windowing mechanism extends each transmit waveform both earlier and later in time thus creating extending waveform portions on either end of the transmit waveform. The extended portions are then multiplied by a suitable windowing function and the result is summed with the next transmit waveform.

Abstract: A novel and useful windowing mechanism for reducing the out of band harmonics of an output transmit signal. The windowing mechanism functions to smooth the transition between two consecutive transmit waveforms. The mechanism of the present invention is particularly useful in communication systems characterized by consecutively transmitted symbols whereby the concatenation of transmitted waveforms causes discontinuities between symbols. The windowing mechanism is operative to reduce the effect of these discontinuities to reduce out of band harmonics of the transmitted output signal. The windowing mechanism extend each transmit waveform both earlier and later in time thus creating extending waveform portions on either end of the transmit waveform. The extended portions are then multiplied by a suitable windowing function and the result is summed with the next transmit waveforms.

Abstract: A novel robust communications scheme whereby a repetition code at the transmitter and an associated cumulative decoder at the receiver are used to increase the reliability of transmission in a communications system. The robust communications scheme of the present invention is effective to increase the reliability of transmission by repetitively transmitting each data segment a number of times in accordance with a repetition code and subsequently collecting the received energy at the receiver over an accordingly longer period of time. Accumulating the received energy over a longer period of time at the receiver, yields a marked improvement in the signal to noise ratio (SNR) of the receiver.