Rf variable gain amplifier using current steering and current cancellation techniques for high resolution rf phase shifters

A phase shifting electronic circuit, comprising:

• a radio frequency (RF) signal input that receives an RF signal;
• a quadrature coupler that splits the received RF signal into in-phase (I) and quadrature (Q) signals;
• a first variable gain amplifier (VGA) configured to receive the in-phase (I) signals, the first VGA including a current cancelling portion and a current steering portion, wherein the current cancelling portion and the current steering portion include a flexible bit architecture for individually configuring a number of bits in each portion;
• a second VGA configured to receive the quadrature (Q) signals, the second VGA including a current cancelling portion and a current steering portion, wherein the current cancelling portion and the current steering portion include a flexible bit architecture for individually configuring a number of bits in each portion;
• and
• an RF out component connected to the first VGA and the second VGA and configured to combine the in-phase (I) and quadrature (Q) signals amplified by the first VGA and the second VGA.

A method comprising:

• providing a variable gain amplifier (VGA) including a n-bit current cancelling portion and a m-bit current steering portion, wherein the current cancelling portion and the current steering portion comprise a flexible bit architecture for individually configuring a number of bits in each portion;
• selecting a number of n-bits for desired gain steps of the current cancelling portion;
• and
• iteratively increasing a number of m-bits until a predetermined phase error is reached.