Abstract: A modem includes a base unit for transmitting a data signal, and a communication card which receives the data signal from the base unit over a wireless medium and which performs echo canceling on the data signal. The base unit is in communication with a telephone line and receives an original signal from the telephone line. The base unit generates an RF modulated signal based on the original signal. The base unit includes a transmitter for transmitting the data signal. Circuitry in the base unit receives the original signal from the telephone line and generates a combined data signal from the original signal and echo signals and maintains a peak voltage of the combined signal which is within the linear amplification region of the transmitter.

Abstract: Circuitry to transmit an analog data signal over a wireless communication link includes a receiver that receives a data signal, an automatic gain control circuit that keeps a peak amplitude of the data signal substantially constant and within a predetermined linear amplification range, and a transmitter, having the predetermined linear amplification range, that receives the data signal from the automatic gain control circuit and that outputs the data signal.

Abstract: A modem includes a base unit for transmitting a data signal, and a communication card which receives the data signal from the base unit over a wireless medium and which performs echo canceling on the data signal. The base unit is in communication with a telephone line and receives an original signal from the telephone line. The base unit generates an RF modulated signal based on the original signal. The base unit includes a transmitter for transmitting the data signal. Circuitry in the base unit receives the original signal from the telephone line and generates a combined data signal from the original signal and echo signals and maintains a peak voltage of the combined signal which is within the linear amplification region of the transmitter.

Abstract: A modem transmits data between a computer and a telephone line. The modem features a base unit which receives a data signal from the telephone line and which transmits the data signal over a wireless link. A device receives the data signal over the wireless link and outputs an analog data signal that corresponds to the data signal. A modem card receives the analog data signal from the device, digitizes the analog data signal to produce a digital signal, demodulates the digital signal, and provides an output digital data signal to the computer.

Abstract: Circuitry to transmit an analog data signal over a wireless communication link includes a receiver that receives a data signal, an automatic gain control circuit that keeps a peak amplitude of the data signal substantially constant and within a predetermined linear amplification range, and a transmitter, having the predetermined linear amplification range, that receives the data signal from the automatic gain control circuit and that outputs the data signal.

Abstract: An apparatus transmits an analog data signal over a wireless communication link. The apparatus includes a base unit having a wired connection to a telephone line. The base unit transmits data to and from the telephone line via the wired connection. The apparatus also includes a remote unit having a wired connection to a modem. The remote unit transmits data to and from the modem via the wired connection. The remote unit and the base unit communicate with each other over the wireless communication link. The base unit includes a radio frequency transmitter to transmit the analog data signal to the remote unit and an automatic gain control circuit that keeps a peak amplitude of the analog data signal substantially constant and within a linear amplification range of the radio frequency transmitter.

Abstract: Errors in communication of a bit stream of information are reduced by incorporating an error checking facility (e.g., parity checking bits) in the information, sending the information on two independent communication channels, and selecting the information sent on one or the other of the two channels based on an error checking analysis of the information sent on both of the channels.

Abstract: In an angle diversity receiving system, the primary and diversity signals are produced by a waveguide signal separator coupled to a single receiving antenna.The separator operates by converting selective higher order modes in the antenna into fundamental modes that will propagate in its two output waveguides. The result is a robust system that operates over a frequency band wide enough to cover both the 4 GHz and 6 GHz common carrier bands with both horizontally and vertically polarized signals, and that can use a wide variety of antennas.

Abstract: In a radio communication system, an adaptive transmitter power control system is described wherein the signal level at each receiver is monitored and a control signal, which is a function of the signal level, is transmitted back to the transmitting station to adjust the transmitter output power, as required. By transmitting the lowest power level consistent with system objectives, the repeater circuits operate in a highly linear mode, and cochannel interference is significantly reduced.