Abstract: According to one aspect of the present disclosure, an ultra-low voltage current reused voltage-controlled oscillator and transconductance-capacitor filter is provided. The circuit includes a voltage-controlled oscillator stacked atop a transconductance-capacitor filter. The voltage-controlled oscillator includes a node one, a node two, a node three, a node four, an inductance, a variable capacitor, a first switched element, a second switched element, a third switched element, and a fourth switched element. The transconductance-capacitor filter includes a first resistor, a second resistor, a fifth switched element, a sixth switched element, a seventh switched element, and an eighth switched element.

Abstract: The present invention discloses a gain-boosted n-path passive-mixer-first receiver. According to another aspect of the present disclosure, a gain-boosted n-path passive-mixer-first receiver is provided. The receiver includes a number n of switch-capacitor (sc) sets, a resistor, and a transconductance amplifier. The sc sets connect in parallel, and the sc sets have a first node and a second node. The resistor connects to the first node. The transconductance amplifier connects to the resistor and the second node.

Abstract: According to one aspect of the present disclosure, an ultra-low voltage current reused voltage-controlled oscillator and transconductance-capacitor filter is provided. The circuit includes a voltage-controlled oscillator stacked atop a transconductance-capacitor filter. The voltage-controlled oscillator includes a node one, a node two, a node three, a node four, an inductance, a variable capacitor, a first switched element, a second switched element, a third switched element, and a fourth switched element. The transconductance-capacitor filter includes a first resistor, a second resistor, a fifth switched element, a sixth switched element, a seventh switched element, and an eighth switched element.

Abstract: According to another aspect of the present disclosure, a radio-frequency-to-baseband-function-reuse receiver with shared amplifiers for common-mode and differential-mode amplification is provided. The receiver includes two set networks connected in parallel. The set networks includes a first and a second input capacitors, a first and a second output capacitors, a first transconductance amplifier having an input terminal, a second transconductance amplifier having an input terminal, a first switch, and a second switch. The first and the second input capacitors connect to a first node. The first and the second output capacitors connect to a second node. The first transconductance amplifier connects between the first input capacitor and the first output capacitor. The second transconductance amplifier connects between the second input capacitor and the second output capacitor. The first switch connects between the input terminal of the first transconductance amplifier and the second node.

Abstract: The present invention discloses a gain-boosted N-path SC bandpass filter (GB-BPF) with a number of sought features. It is based on a transconductance amplifier (Gm) with an N-path SC branch as its feedback network, offering 1) double RF filtering at the input and output of the Gm in one step; 2) customized passband gain and bandwidth with input-impedance match, and 3) reduced physical capacitance thanks to the loop gain offered by Gm. All have been examined using a RLC model of the SC branch before applying the linear periodically time-variant (LPTV) analysis to derive the R, L and C expressions and analytically study the harmonic selectivity, harmonic folding and noise. The latter reveals that: 1) the noise due to the switches is notched at the output, allowing smaller switches to save the LO power; and 2) the noises due to the source resistance and Gm are narrowband at the output, reducing the folded noise during harmonic mixing.

Abstract: A single-ended-input current-reuse wideband receiver comprising (1) a stacked Radio Frequency to Baseband (RF-to-BB) front-end with an 8-path active mixer realizing RF amplification, harmonic-recombination (HR) down-conversion, and BB filtering in the current domain for better linearity and power efficiency; (2) a feedforward 8-path passive mixer enabling LO-defined input impedance matching without external components, while offering frequency-translated bandpass filtering and noise cancelling; (3) a single-MOS pole-zero lowpass filter (LPF) permitting both RF and BB filtering at low voltage headroom consumption, while easing the tradeoff between the in-/out-of-band linearity; and (4) a BB-only two-stage HR amplifier boosting the 3rd and 5th harmonic rejection ratios (HRR3,5) with low hardware intricacy.

Abstract: An IF-noise-shaping transistorized current-mode lowpass filter is applied to quadrature in a balanced circuit. A first pair of transistors receiving current inputs from a mixer are connected so that each of the first pair of transistors has its gate cross coupled to the output of the other of the first pair of transistors. A second pair of transistors are connected in series with respected outputs of respective ones of the first pair of transistors and having gates connected to a first common voltage node, and a capacitance is used to connect the current inputs of one of the first and second pairs of transistors. An active inductive load is connected between the current inputs of one of the first and second pairs of transistors.

Abstract: A digital calibration circuit is used to provide joint-elimination of transmitter and receiver I/Q imbalances. Digital I and Q quadrature signals are received and converted to analog I and Q quadrature signals on I and Q for transmission on output channels. An output mixer is used to convert the quadrature signals to an unbalanced RF output. An unbalanced RF signal is received selectively either externally or from the RF output using a source follower, and the received signal is mixed to provide analog I and Q quadrature signals, using a local oscillator (LO). The LO adds an additional 90 ° phase shift between I and Q quadrature channels of the unbalanced RF input. Parameter estimating the transmitted digital I and Q quadrature signals and providing estimations of I and Q quadrature imbalance conditions.

Abstract: A single-MOS pole-zero lowpass filter for use in a single-ended-input current-reuse wideband receiver having a stacked RF-to-BB front end adapted to receive and process an RF signal to generate an N-phase BB signal, the lowpass filter being adapted to filter the N-phase BB signal, the lowpass filter having a lowpass input impedance for high stopband rejection at low voltage headroom consumption. The lowpass filter is arranged with one active MOS MLPF and one self-biased MOS ML; MLPF creates complex poles and two stopband zeros to boost the stopband rejection; ML provides BB current-to-voltage conversion and common-mode feedback to alleviate tradeoff between voltage headband and BB gain; and ML is diode-connected to enable the generated BB signal to be copied to a next HR stage.

Abstract: A unified balun low noise amplifier (LNA) and I/Q mixer is provided as a single-chip design, and includes a passive/active gain-boosted balun-LNA-I/Q-mixer (blixer), a filter section and a buffer amplifier. The filter section includes an IF-noise-shaping transistorized current-mode lowpass filter sharing a common power supply with the blixer, which allows the blixer and lowpass filter to draw a single bias current. The filter section also includes a complex-pole load providing image rejection and channel selection.

Abstract: A wideband driver amplifier with embedded passive filtering and gain peaking is described. The wideband driver amplifier comprises a voltage to current circuit, a passive band-selection filter, and a current to voltage circuit. The driver amplifier features an Embedded CLC-Ladder band-selection filter and thereby immune to process variations.

Abstract: A complex-pole load is configured as a parallel circuit, having 4 transistors arranged in pairs. Each pair of transistors has a transistor gated by a control voltage sources, and connected in parallel with a transistor diode connected for gating by the respective input. The control voltage sources result in the circuit synthesizing a first order complex pole at a positive IF (+IF) or a negative IF (?IF) for channel selection and image rejection, offering image rejection and channel selection concurrently.

Abstract: A unified balun low noise amplifier (LNA) and I/Q mixer is provided as a single-chip design, and includes a passive/active gain-boosted balun-LNA-I/Q-mixer (blixer), a filter section and a buffer amplifier. The filter section includes an IF-noise-shaping transistorized current-mode lowpass filter sharing a common power supply with the blixer, which allows the blixer and lowpass filter to draw a single bias current. The filter section also includes a complex-pole load providing image rejection and channel selection.

Abstract: An IF-noise-shaping transistorized current-mode lowpass filter is applied to quadrature in a balanced circuit. A first pair of transistors receiving current inputs from a mixer are connected so that each of the first pair of transistors has its gate cross coupled to the output of the other of the first pair of transistors. A second pair of transistors are connected in series with respected outputs of respective ones of the first pair of transistors and having gates connected to a first common voltage node, and a capacitance is used to connect the current inputs of one of the first and second pairs of transistors. An active inductive load is connected between the current inputs of one of the first and second pairs of transistors.

Abstract: A digital calibration circuit is used to provide joint-elimination of transmitter and receiver I/Q imbalances. Digital I and Q quadrature signals are received and converted to analog I and Q quadrature signals on I and Q for transmission on output channels. An output mixer is used to convert the quadrature signals to an unbalanced RF output. An unbalanced RF signal is received selectively either externally or from the RF output using a source follower, and the received signal is mixed to provide analog I and Q quadrature signals, using a local oscillator (LO). The LO adds an additional 90° phase shift between I and Q quadrature channels of the unbalanced RF input. Parameter estimating the transmitted digital I and Q quadrature signals and providing estimations of I and Q quadrature imbalance conditions.

Abstract: One embodiment of the present invention features a poly-phase local oscillator generator combining frequency dividers and direct-injection-locked phase correctors. The poly-phase local oscillator generator comprises a plurality of phase correctors configured to relax frequency and tuning range of a reference local oscillator (LO), and a plurality of frequency dividers, coupled to the phase correctors, configured to offer different frequency segments. The phase correctors are expandable, so that phase accuracy can be optimized by cascading more of themselves.

Abstract: A wireless transmitter for resolving gain mismatch of TV band is disclosed. In one embodiment, a wireless transmitter comprises a two-stage 14-path harmonic-rejection mixer to manage harmonic rejection ratio in lower sub-bands, and a two-stage 6-path harmonic-rejection mixer to manage harmonic rejection ratio in upper sub-bands. The gain mismatch is resolved by selecting gain ratios of the first and the second stage of the two-stage 14-path harmonic-rejection mixer and the two-stage 6-path harmonic-rejection mixer.

Abstract: One embodiment of the present invention features a poly-phase local oscillator generator combining frequency dividers and direct-injection-locked phase correctors. The poly-phase local oscillator generator comprises a plurality of phase correctors configured to relax frequency and tuning range of a reference local oscillator (LO), and a plurality of frequency dividers, coupled to the phase correctors, configured to offer different frequency segments. The phase correctors are expandable, so that phase accuracy can be optimized by cascading more of themselves.

Abstract: A wideband driver amplifier with embedded passive filtering and gain peaking is described. The wideband driver amplifier comprises a voltage to current circuit, a passive band-selection filter, and a current to voltage circuit. The driver amplifier features an Embedded CLC-Ladder band-selection filter and thereby immune to process variations.

Abstract: A wireless transmitter for resolving gain mismatch of TV band is disclosed. In one embodiment, a wireless transmitter comprises a two-stage 14-path harmonic-rejection mixer to manage harmonic rejection ratio in lower sub-bands, and a two-stage 6-path harmonic-rejection mixer to manage harmonic rejection ratio in upper sub-bands. The gain mismatch is resolved by selecting gain ratios of the first and the second stage of the two-stage 14-path harmonic-rejection mixer and the two-stage 6-path harmonic-rejection mixer.