Texas Instruments Corporation

Jeff D Laster

Abdellatif Bellaouar

Charles Gore

Charles Gore, Jr

A wireless communication device (UST), comprising an input for receiving baseband data (I, Q) in a first signal having a first frequency. The device also comprises circuitry () for increasing the first frequency, to form a second signal having a second frequency, in response to a first frequency reference signal (IF), and the device comprises circuitry () for increasing the second frequency, to form a third signal having a third frequency, in response to a second frequency reference signal (LO). Lastly, the device comprises an antenna (ATU) for transmitting the baseband data at a final transmission frequency selected as a band within a predetermined set of frequency bands. With reference to the preceding, the first frequency reference signal and the second frequency reference signal are variable and are selected in response to the final transmission frequency which is a particular band selected as a different band at different times and from the predetermined set of frequency bands.

Wireless communication system with variable intermediate frequency transmitter

Multiple-mode direct phase/amplitude modulation circuitry () for use in a transceiver () of a device such as a wireless handset () is disclosed. The modulation circuitry () includes a modulation loop () for modulating a phase signal into a Gaussian-Minimum-Shift-Keyed (GMSK) signal for transmission in a first mode. The modulation loop () may include a phase-locked loop () with its frequency controlled by a &#x3a3;-&#x394; demodulation of a compensated version of the phase signal, or alternatively may produce a modulated signal from a direct digital synthesis circuit (). An amplitude signal is converted into an analog signal and applied to a single-sideband mixer () for combination with a frequency multiplied version of the phase-modulated signal (GMSK(t); PH(t)), producing an amplitude and phase modulated signal for transmission in a second mode.

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Richardson, TX, United States of America

Jeff D Laster