Jone
Advanced Member level 4
image rejection ratio formula
For the image-reject receiver, I've tried to calculate the IRR due to a departure in phase ΔΦ from the quadrature. It is assumed that the gain of each block is perfectly matched so only imperfect 90° phase shift has to be considered. The formula is expressed as
IRR = 1+4cot(ΔΦ)^2 ≈ 4/(ΔΦ)^2
This formula is stated in Lee's book "Design of CMOS RFIC", in chapter 19 on architectures. The derivation should be pretty simple I think but for some reason I cannot get the same result. Can you refer some source where there is a derivation?
For the image-reject receiver, I've tried to calculate the IRR due to a departure in phase ΔΦ from the quadrature. It is assumed that the gain of each block is perfectly matched so only imperfect 90° phase shift has to be considered. The formula is expressed as
IRR = 1+4cot(ΔΦ)^2 ≈ 4/(ΔΦ)^2
This formula is stated in Lee's book "Design of CMOS RFIC", in chapter 19 on architectures. The derivation should be pretty simple I think but for some reason I cannot get the same result. Can you refer some source where there is a derivation?