Ultra-Low-Power RF Receiver Frontend With Tunable Matching Networks
First Claim
1. A tunable matching, circuit, comprising:
- an input port for receiving an RF input signal via an electrical connection having a parasitic inductance;
an output port;
a switched capacitor circuit coupled to the input port and to ground, the switched capacitor circuit having a first digital control bit input port;
a switched resistor circuit coupled to the input port and the output port, the switched resistor circuit having a first digital control, bit input port; and
a low noise amplifier (LNA) coupled to the input port and the output port, the LNA configured to amplify the RF input signal to form an RF output signal, wherein the LNA is configured to operate in an ultra-low power mode.
1 Assignment
0 Petitions
Accused Products
Abstract
A tunable matching circuit for use with ultra-low power RF receivers is described to support a variety of RF communication bands. A switched-capacitor array and a switched-resistor array are used to adjust the input impedance presented by the operating characteristics of transistors in an ultra-low-power mode. An RF sensor may be used to monitor performance of the tunable matching circuit and thereby determine optimal setting of the digital control word that drives the switched-capacitor array and switched-resistor array. An effective match over a significant bandwidth is achievable. The optimal matching configuration may be updated at any time to adjust to changing operating conditions. Memory may be used to store the optimal matching configurations of the switched capacitor array and switched resistor array.
-
Citations
20 Claims
-
1. A tunable matching, circuit, comprising:
-
an input port for receiving an RF input signal via an electrical connection having a parasitic inductance; an output port; a switched capacitor circuit coupled to the input port and to ground, the switched capacitor circuit having a first digital control bit input port; a switched resistor circuit coupled to the input port and the output port, the switched resistor circuit having a first digital control, bit input port; and a low noise amplifier (LNA) coupled to the input port and the output port, the LNA configured to amplify the RF input signal to form an RF output signal, wherein the LNA is configured to operate in an ultra-low power mode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method, comprising:
-
receiving an RF input signal at an input port of a tunable matching circuit via an electrical connection having a parasitic inductance; adjusting the tunable matching circuit by changing a state of a switched capacitor circuit through receiving input from a first digital control bit input port, the tunable matching circuit being coupled to the input port and to ground; adjusting the tunable matching circuit by changing a state of a switched resistor circuit through receiving input from a second digital control bit input port, the tunable matching circuit being coupled to the input port and to an output port; and amplifying the RF input signal to form an RF output signal by using a low noise amplifier (LNA) coupled to the input port and the output port, wherein the LNA is used in an ultra-low power mode. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A tunable matched RF receiver circuit, comprising:
-
an input port for receiving an RF input signal via an electrical connection having a parasitic inductance; an output port; a switched capacitor circuit coupled to the input port and to ground, the switched capacitor circuit having a first digital control bit input port; a switched resistor circuit coupled to the input port and the output port, the switched resistor circuit having a first digital control bit input port; a low noise amplifier (LNA) coupled to the input port and the output port, the LNA configured to amplify the RF input signal to form an RF output signal; and an in-phase/quadrature down-converter pair coupled to the RF output signal and configured to output an in-phase baseband signal and a quadrature baseband signal, wherein the LNA and the in-phase/quadrature down-converter pair are configured to operate in an ultra-low power mode. - View Dependent Claims (20)
-
Specification