Abstract: The phase locked loop (PLL) frequency synthesizer includes a phase detector receiving a reference signal, a controlled oscillator (e.g. a voltage controlled oscillator) connected to the phase detector and generating a synthesized frequency output signal based upon the reference signal, a mixer (e.g. an in-phase and quadrature-phase (IQ) modulator) connected to the controlled oscillator, a divider connected between the mixer and the phase detector, and a signal source driving the mixer. The frequency synthesizer and method have narrow frequency steps (e.g. as low as fractions of a Hertz) while using a relatively high reference frequency to maintain low phase noise. Furthermore, the fine frequency tuning resolution is achieved while also reducing output spurs and using a relatively simple topology.

Abstract: A novel wireless point to multipoint communication system which maximizes the number of remote stations capable of communicating with a base station is disclosed. Independent gain control of the transmitter on the remote stations as a function of the distance between the remote station and the base station is used. The gain control may be accomplished by attenuators in the RF transmit circuit of the remote stations. The attenuators may be placed immediately preceding the RF amplifiers in the RF transmit circuit of the remote stations. The amount of attenuation of the attenuators may be controlled by a microprocessor. By minimizing the gain from the remote station transmitters, the noise floor of the base station receiver is minimized thereby increasing the performance of the base station receiver. This increase in performance permits more remote stations to communicate with the base station.

Abstract: A novel wireless point to multipoint communication system which maximizes the number of remote stations capable of communicating with a base station is disclosed. Independent gain control of the transmitter on the remote stations as a function of the distance between the remote station and the base station is used. The gain control may be accomplished by attenuators in the RF transmit circuit of the remote stations. The attenuators may be placed immediately preceding the RF amplifiers in the RF transmit circuit of the remote stations. The amount of attenuation of the attenuators may be controlled by a microprocessor. By minimizing the gain from the remote station transmitters, the noise floor of the base station receiver is minimized thereby increasing the performance of the base station receiver. This increase in performance permits more remote stations to communicate with the base station.