Abstract: A frequency hopping, spread spectrum transceiver for wireless data telemetry directly modulates data for transmission using minimum shift keying (MSK) modulation; the transceiver includes a transmit Voltage Controlled Oscillator (VCO) to provide an input to a modulator. A programmable attenuator circuit is used between the source of transmit data, the micro processing unit (MPU), and the transmit phase locked loop (PLL) summing junction. The programmable attenuator provides a selectively attenuated data signal that is coupled to the PLL summing junction to generate a modulated data signal for transmission and dynamically adjusts the transmit data stream voltage level as required to achieve a fixed level in frequency deviation based on the present VCO operating frequency. A complete set of VCO characterization measurements is obtained beforehand.

Abstract: An economical, compact wireless data telemetry transceiver is adapted to establish and maintain communication links at 2.4 GHZ. The wireless transceiver includes RF and computer control components in a compact package approximately the size of a deck of cards and is adapted to be built into original equipment manufacturer (OEM) products to support a wide range of wireless data telemetry applications. Each transceiver includes a shielded RF board or module with a frequency hopping transmitter and receiver, an antenna, and a digital control board or module. The transceiver functions as a half duplex, bi-directional communication device; transmit and receive functions are time interleaved in a non-overlapping fashion. The RF Board consists of a transmitter, receiver, frequency synthesizer and T/R Switch, each controlled by an external microprocessor to either transmit serial data or receive serial data.