Abstract: A 1553 data communication system having a primary data bus, a redundant data bus and a non-1553 data communication overlay system is provided. The non-1553 data communication overlay system comprises a non-1553 bus controller terminal and a non-1553 remote terminal. Each non-1553 terminal includes a non-1553 transmitter block connected to the primary bus and the redundant bus for sending non-1553 signals, a non-1553 receiver block for receiving non-1553 signals and a non-1553 receive path selection block. The non-1553 receive path selection block selectively establishes a receive path between the primary data bus or the redundant data bus and the non-1553 receiver block according to predefined receive path selection criteria. A 1553 data communication method is also provided.

Abstract: A data communication method for a set of hard real-time applications with an associated set of predefined network requirements (PNR) is provided. The method comprises configuring the physical layer of the network with a set of static modulation parameters (SMPs) to guarantee the PNRs are met at worst-case operating conditions for the network. The method further comprises measuring the current network performance within the network based on a given network performance monitoring schedule and, whenever the current network performance exceeds the PNRs by predefined amounts, adjusting the physical layer of the network by selecting a set of dynamic modulation parameters (DMP's) to increase the bandwidth availability within the network. Advantageously, the invention further allows for the allocation of the excess bandwidth to a set of non-hard real-time applications, whenever the current network performance exceeds the PNR.

Abstract: A 1553 data communication system having a primary data bus, a redundant data bus and a non-1553 data communication overlay system is provided. The non-1553 data communication overlay system comprises a non-1553 bus controller terminal and a non-1553 remote terminal. Each non-1553 terminal includes a non-1553 transmitter block connected to the primary bus and the redundant bus for sending non-1553 signals, a non-1553 receiver block for receiving non-1553 signals and a non-1553 receive path selection block. The non-1553 receive path selection block selectively establishes a receive path between the primary data bus or the redundant data bus and the non-1553 receiver block according to predefined receive path selection criteria. A 1553 data communication method is also provided.

Abstract: A 1553 data communication system having a primary data bus, a redundant data bus and a non-1553 data communication overlay system is provided. The non-1553 data communication overlay system comprises a non-1553 bus controller terminal and a non-1553 remote terminal. Each non-1553 terminal includes a non-1553 transmitter block connected to the primary bus and the redundant bus for sending non-1553 signals, a non-1553 receiver block for receiving non-1553 signals and a non-1553 receive path selection block. The non-1553 receive path selection block selectively establishes a receive path between the primary data bus or the redundant data bus and the non-1553 receiver block according to predefined receive path selection criteria. A 1553 data communication method is also provided.

Abstract: A system and method for allocating transmitter power to subcarriers of a multicarrier signal is provided. First, the subcarriers are transmitted with an initial set of power levels and an initial set of constellation assignments. Next, quantized SNR metric values are measured at the receiver for each subcarrier. The measured subcarrier quantized SNR metric is compared with the respective allocated constellation quantized SNR metric, for determining the excess SNR per subcarrier. The transmitter power of the subcarriers whose excess SNR is above a predetermined threshold is adjusted, while keeping the total transmitter power constant. The transmitter power may be adjusted for increasing throughput or robustness of the system. For increased accuracy, several training frames may be used. Advantageously, only constellations equally spaced, such as square or cross constellations, are used. According to a preferred embodiment, OFDM/DMT multicarrier system use IFFT prescalers in the transmitter power adjustment.

Abstract: An orthogonal linear frequency modulation (OLFM) communications system has an OFDM transmitter and receiver communcating data on a series of multiplexed sub-carriers over a communications medium. A linear frequency modulator provided at the transmitter subjects the sub-carriers to linear frequency modulation to produce a series of sub-sweeps for transmission over the communications medium. A linear frequency demodulator at the receiver produces the sub-carriers from the received sub-sweeps for subsequent demodulation to recover the data.

Abstract: An orthogonal linear frequency modulation (OLFM) communications system where orthogonal sub-sweeps experience the same channel condition and subsequent SNR allowing for uniform power allocation and data modulation per sub-sweep and an efficient exchange of modulation parameters for more optimized communications.

Abstract: A 1553 data communication system having a primary data bus, a redundant data bus and a non-1553 data communication overlay system is provided. The non-1553 data communication overlay system comprises a non-1553 bus controller terminal and a non-1553 remote terminal. Each non-1553 terminal includes a non-1553 transmitter block connected to the primary bus and the redundant bus for sending non-1553 signals, a non-1553 receiver block for receiving non-1553 signals and a non-1553 receive path selection block. The non-1553 receive path selection block selectively establishes a receive path between the primary data bus or the redundant data bus and the non-1553 receiver block according to predefined receive path selection criteria. A 1553 data communication method is also provided.

Abstract: An interference cancellation (IC) system and method for use within a 1553 communication system comprising a data bus carrying primary signals having a 1553 component and a non-1553 component are provided. The IC system has an input port, a 1553 data extraction block and an interference cancellation circuit with an interference measurement and a cancellation block. The interference measurement block receives 1553 decoded data from the 1553 data extraction block and a sampled primary signal via the input port, and, within an impulse response block, produces an interference signal based on a 1553 impulse response system model. The cancellation block subtracts the interference signal from the sampled primary signal and produces an output signal with the 1553 component substantially cancelled. Furthermore, an IC system using adaptive filtering techniques within the impulse response block is provided. The Least Mean Squares (LMS) algorithm can be used as an adaptive filter technique.

Abstract: A communications system permits bandwidth configurability using a linear frequency modulated (LFM) waveform for transmitter/receiver synchronization. The system permits enhancement of MIL-STD-1553 data buses, and is likewise applicable to any bandwidth-configurable modem.

Abstract: An interference cancellation system and method for a communication system comprising a data bus carrying primary signals having an A component and a non-A component are provided. The interference cancellation system has an input port, an A data extraction block and an interference cancellation circuit. The input port receives a sampled primary signal from the data bus, via an analog-front end block having sampling means. The A data extraction block extracts A data from the sampled primary signal and outputs A decoded data. The interference cancellation circuit has an interference measurement block and a cancellation block. The interference measurement block receives the A decoded data and the sampled primary signal and produces an A interference signal. The cancellation block receives the sampled primary signal and the A interference signal and subtracts the A interference signal from the sampled primary signal, producing an output signal with the A component substantially attenuated.

Abstract: An interference cancellation system and method for a communication system comprising a data bus carrying primary signals having an A component and a non-A component are provided. The interference cancellation system has an input port, an A data extraction block and an interference cancellation circuit. The input port receives a sampled primary signal from the data bus, via an analog-front end block having sampling means. The A data extraction block extracts A data from the sampled primary signal and outputs A decoded data. The interference cancellation circuit has an interference measurement block and a cancellation block. The interference measurement block receives the A decoded data and the sampled primary signal and produces an A interference signal. The cancellation block receives the sampled primary signal and the A interference signal and subtracts the A interference signal from the sampled primary signal, producing an output signal with the A component substantially attenuated.

Abstract: A synchronization system and method for use in a packet switched communication network are provided. The synchronization system comprises a transmitter-identification system, a packet-boundary detection system and a storage-access system. The transmitter-identification system enables each receiving terminal within the network to know the identity of the originating transmitter terminal for a given packet of information, prior to the reception of this packet of information. The packet-boundary detection system enables detection of packet synchronization parameters for all transmitter-receiver pairs of terminals within the network. The storage-access system stores the detected packet synchronization parameters and allows the receiver to access the packet synchronization parameters.

Abstract: A data communication method for a set of hard real-time applications with an associated set of predefined network requirements (PNR) is provided. The method comprises configuring the physical layer of the network with a set of static modulation parameters (SMPs) to guarantee the PNRs are met at worst-case operating conditions for the network. The method further comprises measuring the current network performance within the network based on a given network performance monitoring schedule and, whenever the current network performance exceeds the PNRs by predefined amounts, adjusting the physical layer of the network by selecting a set of dynamic modulation parameters (DMP's) to increase the bandwidth availability within the network. Advantageously, the invention further allows for the allocation of the excess bandwidth to a set of non-hard real-time applications, whenever the current network performance exceeds the PNR.

Abstract: A system and method for allocating transmitter power to subcarriers of a multicarrier signal is provided. First, the subcarriers are transmitted with an initial set of power levels and an initial set of constellation assignments. Next, quantized SNR metric values are measured at the receiver for each subcarrier. Following, the measured subcarrier quantized SNR metric is compared with the respective allocated constellation quantized SNR metric, for determining the excess SNR per subcarrier. The transmitter power of the subcarriers whose excess SNR is above a predetermined threshold is adjusted, while keeping the total transmitter power constant. The process may be repeated until a set of predefined expectations is met. The transmitter power may be adjusted for increasing throughput or robustness of the system. For increased accuracy of SNR measurements via BER estimation, several training frames may be used. Advantageously, only constellations equally spaced, such as square or cross constellations, are used.

Abstract: A synchronization system and method for use in a packet switched communication network are provided. The synchronization system comprises a transmitter-identification system, a packet-boundary detection system and a storage-access system. The transmitter-identification system enables each receiving terminal within the network to know the identity of the originating transmitter terminal for a given packet of information, prior to the reception of this packet of information. The packet-boundary detection system enables detection of packet synchronization parameters for all transmitter-receiver pairs of terminals within the network. The storage-access system stores the detected packet synchronization parameters and allows the receiver to access the packet synchronization parameters.

Abstract: An interference cancellation (IC) system and method for use within a 1553 communication system comprising a data bus carrying primary signals having a 1553 component and a non-1553 component are provided. The IC system has an input port, a 1553 data extraction block and an interference cancellation circuit. The interference cancellation circuit has an interference measurement and a cancellation block. The interference measurement block receives 1553 decoded data from the 1553 data extraction block and a sampled primary signal via the input port, and, within an impulse response block, produces an interference signal based on a 1553 impulse response system model. The cancellation block subtracts the interference signal from the sampled primary signal and produces an output signal with the 1553 component substantially cancelled. Furthermore, an IC system using adaptive filtering techniques within the impulse response block is provided.

Abstract: A 1553 data communication system having a primary data bus, a redundant data bus and a non-1553 data communication overlay system is provided. The non-1553 data communication overlay system comprises a non-1553 bus controller terminal and a non-1553 remote terminal. Each non-1553 terminal includes a non-1553 transmitter block connected to the primary bus and the redundant bus for sending non-1553 signals, a non-1553 receiver block for receiving non-1553 signals and a non-1553 receive path selection block. The non-1553 receive path selection block selectively establishes a receive path between the primary data bus or the redundant data bus and the non-1553 receiver block according to predefined receive path selection criteria. A 1553 data communication method is also provided.

Abstract: An analog signal gain control circuit(ASGC) for a digital radio HomePlug orthogonal frequency division multiplexing (OFDM) receiver includes a digital variable gain amplifier (DVGA) to control the gain of a received signal to achieve a desired signal amplitude to match a dynamic range of an analog-to-digital converter (ADC), an inverse scaling stage controlled to inverse-scale the signal output by the ADC, and a two-stage fast attack and slow decay filter that outputs control signals to the DVGA and to the inverse scaling stage. The fast attack and slow decay filter rapidly responds to an increase in signal amplitude and slowly decays the amplitude of the control signal in response to a decrease in input signal amplitude.

Abstract: A communications system permits bandwidth configurability using a linear frequency modulated (LFM) waveform for transmitter/receiver synchronization. The system permits enhancement of MIL-STD-1553 data buses, and is likewise applicable to any bandwidth-configurable modem.