Abstract: The invention provides an automatic gain control system that is implemented by digital hardware. The digital hardware determines the range of a set of digital data values, and then examines each digital data value in a sequence. An index counter increments a sample count index i each time a new digital data value is examined and determines the absolute value of the ith digital data value. The digital hardware also counts both the number j of digital data values that exceed a high percentage value of the range, and the number k of digital data values that are less than a low percentage value of the range as the digital hardware runs through the sequence. If the digital hardware determines that a digital data value is greater than the high percentage value, the ratio j/i exceeds a first threshold value, and the gain level is not set to the lowest gain level, then the gain is decreased.

Abstract: A communications node includes a controller for 1) initializing a counter and resetting a FIFO buffer; 2) determining if a predetermined number of data packets have been transmitted; 3) transmitting the data packets after the FIFO buffer is partially filled if the number of data packets transmitted is less than the predetermined number, incrementing the counter, and returning to step (2); 4) directing a transceiver to be in a receive mode if the predetermined number of data packets have been transmitted; 5) determining if a command signal has been detected; 6) processing a backlink command if a command signal has been detected, and then directing the transceiver to be in transmit mode, clearing the counter, and returning to step(2); and 7) setting the receiver in a transmit mode if no command signal has been detected, and then clearing the counter and returning to step (2).

Abstract: A buoyed sensor array communications system comprises multiple sensor syss electrically connected to a signal transmission line which are positioned at predetermined locations along the signal transmission line to form a linear sensor array. Each of the sensor systems generates a data signal in response to receiving an address signal. The system further includes; a processor system electrically connected to the signal transmission line for transmitting address signals to enable any one of the sensor systems at a time in a selectively accessed order and has a data storage memory for storing the data signal from each of the sensor systems as stored data. A radio frequency transmitting system is coupled to the data processor and transmits the stored data at a predetermined time. A negatively buoyant structure connected to the signal transmission line pulls the communications system to the bottom of a body of water upon deployment.

Abstract: A buoyed sensor array communications system comprises multiple sensor syss electrically connected to a signal transmission line which are positioned at predetermined locations along the signal transmission line to form a linear sensor array. Each of the sensor systems generates a data signal in response to receiving an address signal. The system further includes; a processor system electrically connected to the signal transmission line for transmitting address signals to enable any one of the sensor systems at a time in a selectively accessed order and has a data storage memory for storing the data signal from each of the sensor systems as stored data. A radio frequency transmitting system is coupled to the data processor and transmits the stored data at a predetermined time. A negatively buoyant structure connected to the signal transmission line pulls the communications system to the bottom of a body of water upon deployment.