Frequency translation and applications of same are described herein, including wireless local area network (WLAN) applications such as IEEE Standard 802.11 WLANs. Such applications include, but are not limited to, frequency down-conversion, frequency up-conversion, enhanced signal reception, unified down-conversion and filtering, and combinations and applications of same.

Wireless local area network (WLAN) technology and applications including techniques of universal frequency translation

A transceiver for transmitting and receiving signals includes a transmitter operative to up-convert baseband signals from a baseband frequency into RF signals at a radio frequency (RF) frequency and output the RF signals, a receiver operative to receive RF signals and down-convert the RF signals into baseband signals having the baseband frequency, and a plurality of calibration paths coupling the transmitter to the receiver. Any of the calibration paths can be selected to be active when calibrating components of the transceiver. Tunable components can use calibration information to optimize transceiver performance.

Direct-conversion transceiver enabling digital calibration

Systems and methods for assigning a short codes to provide uniformity among wireless carriers. In the systems and methods, a Universal Short Code (USC) Administrator maintains a list of short codes and their lease status so that SMS messages sent to a particular short code may be routed to the proper holder of the short code. A network facilitator is in communication with both the USC Administrator and at least one wireless carrier to route the SMS message to the proper holder of the short code. The short code may be leased for a specified period of time so that the short code can be reassigned after expiration of the lease.

Universal short code administration facility

A multiple mode RF communication device (100), such as a transmitter, receiver or transceiver, has a first RF communication resource (102, 122) that communicates by default using a first communication mode. A second RF communication resource (104, 124) communicates by default using a second communication mode. A system manager (110) deploys the first and second communication resources according to a set of deployment rules, wherein the deployment rules may be dependent upon a communication quality parameter, priorities, availability of the first and second communication resources as well as other parameters.

Multiple mode rf communication device

Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting and up-converting an electromagnetic (EM) signal are described herein. Briefly stated, in embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In an embodiment, the EM signal is down-converted to an intermediate frequency (IF) signal. In another embodiment, the EM signal is down-converted to a baseband information signal. In another embodiment, the EM signal is a frequency modulated (FM) signal, which is down-converted to a non-FM signal, such as a phase modulated (PM) signal or an amplitude modulated (AM) signal. Up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency.

Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same

This disclosure relates to radio frequency (RF) power converters and methods of operating the same. In one embodiment, an RF power converter includes an RF switching converter, a low-drop out (LDO) regulation circuit, and an RF filter. The RF filter is coupled to receive a pulsed output voltage from the RF switching converter and a supply voltage from the LDO regulation circuit. The RF filter is operable to alternate between a first RF filter topology and a second RF filter topology. In the first RF filter topology, the RF filter is configured to convert the pulsed output voltage from a switching circuit into the supply voltage. The RF filter in the second RF filter topology is configured to filter the supply voltage from the LDO regulation circuit to reduce a ripple variation in a supply voltage level of the supply voltage. As such, the RF filter provides greater versatility.

Multiple mode RF power converter

A method (and apparatus) of receiving (and transmitting) a wanted
modulated radio frequency signal and of demodulating it to recover the
wanted modulating signal (131,132) therefrom, the method comprising
the steps of receiving a radio frequency signal (99); generating a high
frequency local oscillator signal (71,72), which can be mathematically
described as having a fixed frequency ω RF corresponding to the frequency
of the carrier wave of the wanted modulated radio frequency signal and
a phase  ss which varies in time according to a predetermined phase
function; mixing the received radio frequency signal (99) with the high
frequency local oscillator signal (71,72) to generate a mixed signal
(111,116); converting the mixed signal from an analogue signal into a
digital signal (121,122); generating a low frequency local oscillator
signal (61,62,63,64), which can be mathematically described as having a
fixed frequency of zero and a phase  ss which varies in time according to
the predetermined phase function when delayed by a predetermined
delay corresponding to the time taken for the signal to propagate
between the first mixing step (110,115) and the second mixing step (300);
and mixing the mixed signal with the low frequency local oscillator
signal to recover a recovered signal (131,132) including both a wanted
base-band signal whose phase is not dependent on the predetermined
phase function and a noise signal whose phase is dependent upon the
predetermined phase function.

Method and apparatus for radio communication

A parallel amplifier and a parallel amplifier power supply are disclosed. The parallel amplifier power supply provides a parallel amplifier power supply signal, which is adjustable on a communications slot-to-communications slot basis. During envelope tracking, the parallel amplifier regulates an envelope power supply voltage based on the parallel amplifier power supply signal.

Communications based adjustments of a parallel amplifier power supply

A method for demodulating a radio frequency signal having a frequency (f), by
oscillating a demodulator (70) at a frequency (F) different from the signal
frequency (f), and measuring a DC offset value at this different frequency (F), the
DC offset value being associated with interference. Then the demodulator (70) is
oscillated at the signal frequency (f), thereby providing a demodulated signal. The
DC offset value is subtracted from the demodulated signal in order to provide
demodulated signal with a substantially reduced DC component. The
demodulated signal is then monitored for further DC offset components, and these
further DC offset components are subtracted from the demodulated signal.

DC offset cancellation in a quadrature receiver

of EP0939495A portable electronic device operable in an active mode or an inactive mode comprises a first device operating system (109) for performing device operating functions during the active mode but not the inactive mode and a second device operating system (121) for performing device operating functions during both the active mode and the inactive mode. The first device operating system (109) includes a CPU (111) integrated on a first integrated circuit with a first timing circuit (148) for providing a first timing signal. The second device operating system (121) includes a second timing circuit (134) for generating a second timing signal during at least the inactive mode and being integrated on a second integrated circuit, and a power control circuit (128) coupled to receive the second timing signal for generating a first control signal for deactivating the first device operating system (109) for the inactive mode and for generating a second control signal for activating the first device operating system (109) for the active mode.

Nadim Khlat

Papers

Multiple mode RF power converter

Method and apparatus for radio communication

Communications based adjustments of a parallel amplifier power supply

DC offset cancellation in a quadrature receiver

Power saving system for an electronic portable device