Abstract: An apparatus, a carrier medium storing instructions to implement a method, and a method for controlling the gain of a radio receiver for receiving packets of information in a wireless network. The receiver is connected to an antenna subsystem and has receive signal path including a plurality of sections including a first section coupled to the antenna subsystem and a next section. Each section has an adjustable gain and is able to provide a measure of the signal strength at its output. The method includes waiting for a start of packet indication, providing a measure of the signal strength at the output of the first section and the next section, and adjusting the gains of the first and the next sections using the provided measured signal strengths. In one embodiment, the receive signal path includes a filter, the provided measure for the first section is before the filter, and the provided measure for the second section is after the filter.

Abstract: A monolithic radio integrated circuit includes a substrate, a set of one or more analog subcircuits on the substrate, a programmable bias current supply on the substrate coupled to the set to provide bias currents to the analog subcircuits of the set including programmable bias currents to one or more analog subcircuits forming a first subset of the set, and a digital subsection coupled to the programmable bias supply to determine the bias currents supplied to the analog subcircuits of the first subset, such that one or more characteristics of the radio integrated circuit are modifiable by programming the programmable bias supply.

Abstract: An apparatus in a node of a wireless network for setting the data rate for sending data to a remote node, and a method for setting the data rate. The method includes receiving a packet from the remote node, determining a measure of signal quality for the received packet; and selecting the data rate for communicating to the remote node according to at least the determined signal quality. The measure of signal quality is a measure of the EVM of the received packet. One implementation conforms to one or more variants of the IEEE 802.11 standard that uses OFDM packets.

Abstract: A digital AGC system for burst operation, particularly suited for receiving packets in a wireless local area network. One embodiment includes a log detector that provides a signal strength measure, called the received signal strength indication (RSSI) over a wide dynamic range. The AGC system includes estimating the power in a received signal by averaging the log of the signal power. The Start of Packet detection avoids using the radio receiver's main analog to digital converters to preserve power.

Abstract: An apparatus, a carrier medium storing instructions to implement a method, and a method for controlling the gain of a radio receiver for receiving packets of information in a wireless network. The receiver is connected to an antenna subsystem and has receive signal path including a plurality of sections including a first section coupled to the antenna subsystem and a next section. Each section has an adjustable gain and is able to provide a measure of the signal strength at its output. The method includes waiting for a start of packet indication, providing a measure of the signal strength at the output of the first section and the next section, and adjusting the gains of the first and the next sections using the provided measured signal strengths. In one embodiment, the receive signal path includes a filter, the provided measure for the first section is before the filter, and the provided measure for the second section is after the filter.

Abstract: A digital AGC system for burst operation, particularly suited for receiving packets in a wireless local area network. One embodiment includes a log detector that provides a signal strength measure, called the received signal strength indication (RSSI) over a wide dynamic range. The AGC system includes estimating the power in a received signal by averaging the log of the signal power. The Start of Packet detection avoids using the radio receiver's main analog to digital converters to preserve power.

Abstract: A monolithic radio integrated circuit includes a substrate, a set of one or more analog subcircuits on the substrate, a programmable bias current supply on the substrate coupled to the set to provide bias currents to the analog subcircuits of the set including programmable bias currents to one or more analog subcircuits forming a first subset of the set, and a digital subsection coupled to the programmable bias supply to determine the bias currents supplied to the analog subcircuits of the first subset, such that one or more characteristics of the radio integrated circuit are modifiable by programming the programmable bias supply.

Abstract: An apparatus in a node of a wireless network for setting the data rate for sending data to a remote node, and a method for setting the data rate. The method includes receiving a packet from the remote node, determining a measure of signal quality for the received packet; and selecting the data rate for communicating to the remote node according to at least the determined signal quality. The measure of signal quality is a measure of the EVM of the received packet. One implementation conforms to one or more variants of the IEEE 802.11 standard that uses OFDM packets.

Abstract: A frequency synthesizer, a calibrator thereof, and an operating controller thereof are described. The synthesizer comprises a main charge pump that drives a voltage controlled oscillator (VCO) through a loop filter. The calibrator includes a second, replica charge pump that can also drive the VCO, but is set up to output only its maximum or minimum analog output control voltage. Since the construction and characteristics of the replica charge pump duplicate the main charge pump, the main charge pump's minimum and maximum analog control outputs can be cloned out to the VCO on demand. A VCO calibration procedure therefore includes switching the VCO to each of its ranges set by a bank of fixed capacitors, and using the replica charge pump to drive the VCO to its minimum and maximum frequency for each range setting.

Abstract: A phase locked loop (PLL) frequency synthesizer includes a voltage controlled oscillator (VCO) to provide a VCO frequency signal, a frequency offset circuit including a mixer accepting the VCO frequency signal and a signal from a second oscillator to produce a shifted-frequency signal having a frequency significantly lower than the VCO output frequency, a programmable divider accepting the shifted-frequency signal and dividing the frequency of the shifted-frequency signal by a settable amount, a phase detector to compare the phase of the output of the programmable divider to that of a reference oscillator and produce a phase difference signal; and a loop filter to filter a function of the phase difference to produce a control input to the VCO. The offset circuit shifts down the frequency without increasing the divide ratio of the loop as would a prescaler achieving the same frequency conversion as the frequency offset circuit.

Abstract: A frequency synthesizer, a calibrator thereof, and an operating controller thereof are described. The synthesizer comprises a main charge pump that drives a voltage controlled oscillator (VCO) through a loop filter. The calibrator includes a second, replica charge pump that can also drive the VCO, but is set up to output only its maximum or minimum analog output control voltage. Since the construction and characteristics of the replica charge pump duplicate the main charge pump, the main charge pump's minimum and maximum analog control outputs can be cloned out to the VCO on demand. A VCO calibration procedure therefore includes switching the VCO to each of its ranges set by a bank of fixed capacitors, and using the replica charge pump to drive the VCO to its minimum and maximum frequency for each range setting.

Abstract: A frequency synthesizer, a calibrator thereof, and an operating controller thereof are described. The synthesizer comprises a main charge pump that drives a voltage controlled oscillator (VCO) through a loop filter. The calibrator includes a second, replica charge pump that can also drive the VCO, but is set up to output only its maximum or minimum analog output control voltage. Since the construction and characteristics of the replica charge pump duplicate the main charge pump, the main charge pump's minimum and maximum analog control outputs can be cloned out to the VCO on demand. A VCO calibration procedure therefore includes switching the VCO to each of its ranges set by a bank of fixed capacitors, and using the replica charge pump to drive the VCO to its minimum and maximum frequency for each range setting.