Telefonaktiebolaget Lm Ericsson (publ)

Nokia Corporation

St-ericsson Sa

Jarkko Jussila

Pete Sivonen

Sami Vilhonen

Jussi Ryynänen

Jouni Kaukovuori

Jonne Juhani Riekki

An amplifier for converting a single-ended input signal to a differential output signal. The amplifier comprises a first transistor, a second transistor, a third transistor and a fourth transistor. The first transistor, configured in common-source or common-emitter mode, receives the single-ended input signal and generates a first part of the differential output signal. The second transistor, also configured in common-source or common-emitter mode, generates a second part of the differential output signal. The third and fourth transistors are capacitively cross-coupled. The amplifier further comprises inductive degeneration such that a source or emitter of the first transistor is connected to a first inductor and a source or emitter of the second transistor is connected to a second inductor.

Low noise amplifier circuit

A resistor network comprises one or more switched resistor branches. Each switched resistor branch comprises a first resistor connected in series with a first switch, wherein a first terminal of the first resistor is connected to the input terminal of the resistor network, a second terminal of the first resistor is connected to a first terminal of the first switch forming a middle node, and a second terminal of the first switch is connected to the output terminal of the resistor network. Each switched resistor branch further comprises a second resistor connected in series with a second switch, wherein the series connected second resistor and second switch is connected between the middle node and a third terminal of the one or more switched resistor branches. The resistor network further comprises a third resistor connected between the input and output terminals of the resistor network.

Resistor network and mixer circuits with programmable gain

The method and apparatus described herein address problems associated with conventional wireless receivers configured for intra-band carrier aggregation. The disclosed solution applies the received signal to a single front-end amplifier, which may comprise a low-noise amplifier, and divides the amplified signal into two or more processing paths, where each path is associated with a different local oscillator frequency corresponding to a different reception band. To compensate for the impact of the additional processing paths on the amplifier performance, a negative resistor unit applies a negative resistance to the output of the front-end amplifier when two or more processing paths are active.

RF front-end for intra-band carrier aggregation

The method and apparatus disclosed herein reduces the power consumption of a wireless transceiver by reducing the power consumption associated with the corresponding wireless receiver. Generally, a power mode selection unit enables or disables a low power mode based on a dynamic range requirement for the receiver. More particularly, when the dynamic range requirement is less than or equal to a threshold, the power mode selection unit lowers the transconductance of an RF front-end amplifier in the receiver and enables a negative resistance at an output of the RF front-end amplifier. When enabled, the negative resistance compensates for the gain lost by lowering the transconductance of the RF front-end amplifier, which enables the front-end gain associated with the low-power mode to be maintained relative front-end gain associated with the normal mode.

Power consumption reduction technique for integrated wireless radio receiver front-ends

An integrated circuit for a radio receiver comprising a radio-frequency amplifier and a radio-frequency filter is described. The amplifier receives radio-frequency signals from an antenna, the filter is connected to the amplifier output, and the output of the filter is provided to a processing stage of the receiver. The amplifier comprises an amplifying stage controlled by a radio-frequency input signal and a signal fed back from the filter. The amplifier input impedance is substantially matched to the antenna impedance at a frequency band of interest. The signal fed back from the filter providing attenuation of signals outside the frequency band of interest at the amplifier input. The filter comprises one or more filter components. A filter component comprises a first input and a second input for receiving the amplifier output, a first switch arranged to selectively connect the first input to a first impedance, a second switch arranged to selectively connect the first input to a second impedance, a third switch arranged to selectively connect the second input to the first impedance, and a fourth switch arranged to selectively connect the second input to the second impedance. The first and fourth switches are controlled by a first oscillator signal and the second and third switches are controlled by a second oscillator signal that is 180&#xb0; out of phase with the first oscillator signal.

Amplifier with on-chip filter

Disclosed is a multi-mode radio frequency amplifier. The amplifier includes a plurality of input transistors, a plurality of output branches, and a switching stage interposed between the plurality of input transistors and the plurality of output branches for selectively connecting the plurality of input transistors to the plurality of output branches. Individual ones of operational modes of the multi-mode amplifier correspond to an individual one of the plurality of frequency selective loads. A particular one of the plurality of frequency selective loads is one of operating or non-operating during operation of the multi-mode amplifier. A gain of the multi-mode amplifier is reduced by controlling the plurality of elements to steer a predetermined portion of a total signal current that is output from one of the input transistors, from an associated operating frequency selective load to a non-operating frequency selective load.

Amplifier and amplifier gain adjustment circuitry using current steering, and multimode communication device containing same

The present invention relates to a method and circuit arrangement for adjusting a gain, wherein said circuit arrangement comprises at least a first output branch connected to a first load and a second output branch connected to a second load. The gain control function is realized based on a current splitting, wherein a non-operated output branch is used as a kind of dummy branch for receiving a part of the output current. Thus, only as many output branches as there are outputs are required to implement a gain control based on splitting. Thereby, a complexity of the layout design is reduced and control and biasing of dummy branches is not required.

Growing community of inventors

Turku, Finland

Jarkko Jussila