Patent ID: 8368481

Claim:
A switchable balun comprising: a. a primary winding operatively coupled to a second port and a third port, wherein i. said second port is operatively coupled to a low noise amplifier; and ii. said third port is operatively coupled to a power amplifier, b. a secondary winding operatively coupled to a first port, wherein said first port is operatively coupled to an antenna; and c. a first variable capacitor in parallel with said secondary winding, said first variable capacitor configured to transform the impedance seen by said primary winding so that the impedance at said second port and said third port is smaller than the impedance at said first port, wherein when said switchable balun is in a first state, said first port is coupled to said second port, when said switchable balun is in a second state, said first port is coupled to said third port, and wherein the ratio of said primary winding to said secondary winding is at least greater than or equal to a one-to-one ratio.