Sampling mixer with asynchronous clock and signal domains
AssigneeTexas Instruments Incorporated
InventorsRobert B. Staszewski, Khurram Muhammad, Yo-Chuol Ho, Dirk Leipold
Life of this patent
Estimating the term…
Abstract
A mixer 1100 with a plurality of signal paths typically requires separate clock generating hardware for each signal path. However, the redundancy of having multiple clock generating hardware significantly increases power consumption and integrated circuit area when the mixer 1100 is integrated into silicon. A method and apparatus 1125 containing a circuit for generating a set of clock signals that can be shared by the different signal paths is presented. Advantage is taken of the significant capacitance difference between different sampling capacitors in the mixer and the superposition property.
Claims56
A method for generating clock signals for use in activating and deactivating rotating capacitors in a receiver mixer with a plurality of signal paths to sample a received data signal, the method comprising:
- producing a reference signal;
- generating a set of clock signals from the reference signal;
- and
- distributing the set of clock signals to the plurality of signal paths, wherein the set of clock signals are used to activate and deactivate rotating capacitors in each of the signal paths.
A circuit for generating a set of clock signals for use in activating and deactivating rotating capacitors in a radio receiver with a plurality of signal paths, the circuit comprising:
- a reference signal generator to generate a clock signal at a specified frequency;
- a clock divider coupled to the reference signal generator, the divider containing circuitry to divide the clock signal to change the frequency of the clock signal;
- and
- a clock generator coupled to the clock divider, the clock generator containing circuitry to output the set of clock signals to the plurality of signal paths.
A radio receiver comprising:
- an radio frequency (RF) input to receive RF signals;
- a current-mode sampling mixer coupled to the RF input, the mixer comprising:
- a plurality of signal paths, each signal path coupled to the RF input and a local oscillator, the signal path containing circuitry to sample a received signal provided by the RF input and to output a discrete-time sample stream;
- a timing circuit coupled to the plurality of signal paths, the timing circuit containing circuitry to control the operation of the signal paths;
- and
- a signal processing circuit coupled to the mixer, the signal processing circuit containing circuitry to transform output produced by the plurality of signal paths into user usable data.
A wireless communications device comprising:
- an antenna to receive and transmit radio frequency (RF) signals;
- a RF receiver coupled to the antenna, the RF receiver containing circuitry to convert RF signals into a data stream, the RF receiver comprising a current-mode sampling mixer, the current-mode sampling mixer comprising:
- a plurality of signal paths, each signal path coupled to the antenna and a local oscillator, the signal path containing circuitry to sample a received signal provided by the antenna and produce a discrete-time sample stream of the received signal;
- a timing circuit coupled to the plurality of signal paths, the timing circuit containing circuitry to control the operation of the signal paths;
- a digital baseband (DBB) controller coupled to the RF transceiver, the DBB controller containing circuitry to digitally process the data stream provided by the RF transceiver and convert it into user usable data;
- and
- a memory coupled to the DBB controller, the memory containing storage elements to store data and programs.
Dependencies are inferred from the claim text.