Low noise amplifier and receiver

A low noise amplifier comprising:

• at least one input port configured to receive a carrier as an input signal;
• first to n-th output ports connected to n load circuits, respectively, n is a natural number greater than or equal to 2;
• a first amplifier stage comprising a first gain stage connected to the input port and configured to amplify the input signal and n drive stages connected to the first to nth output ports, respectively;
• and
• second to n-th amplifier stages, each comprising a second gain stage connected to the input port and configured to amplify the input signal and a cascode transistor connected between one of the second to nth output ports and an output terminal of the gain stage and configured to transmit the amplified input signal to the load circuit corresponding to the output port,
• wherein each of the first gain stage and the second gain stage comprises
• an input capacitor having one end connected to the input port,
• a degeneration inductor having one end connected to a ground terminal, and
• an input transistor having a gate connected to the other end of the input capacitor and connected between an input node of the drive stage and the other end of the degeneration inductor, and
• the input transistor is configured to vary an impedance so that an input impedance and a parasitic impedance are uniform regardless of an operation mode.

A receiver capable of wireless communication, comprising:

• switches/duplexers configured to route a transmission/reception input signal;
• input circuits configured to provide the routed input signal by performing power and impedance matching;
• a low noise amplifier configured to provide first to third output signals by amplifying the provided input signal;
• and
• first to third load circuits configured to receive the first to third output signals, respectively,
• wherein the low noise amplifier comprises
• a first amplifier stage connected between an input port through which the input signal is received and the first to third load circuits;
• a second amplifier stage connected between the input port and the second load circuit;
• and
• a third amplifier stage connected between the input port and the third load circuit, and
• the first to third amplifier stages are configured to vary an input transistor so that the low noise amplifier has a uniform input impedance regardless of an operation mode of the low noise amplifier.