System and method for an image rejecting single conversion tuner with phase error correction

A single conversion radio frequency (“RF”) tuner for converting a received RF signal into an intermediate frequency (“IF”) output signal, said tuner comprising:

• image rejection circuitry comprising separate in-phase (“I”) and quadrature-phase (“Q”) signal paths, wherein said I and Q signals are phase shifted and summed to substantially cancel an image channel from said signals;
• and
• phase error correction circuitry for measuring a phase error between said I and Q signal paths and adjusting the relative phase of said I and Q signal paths to substantially remove said phase error;
• wherein said image rejection circuitry further comprises:
• a primary frequency synthesizer providing a primary local oscillator (“LO”);
• a +45 degree LO phase shifter having a input coupled to said LO;
• a −45 degree LO phase shifter having a input coupled to said LO;
• wherein said I signal path further comprises
• an I signal mixer having a first input coupled to said received RF signal and a second input coupled to said +45 degree LO phase shifter;
• and
• a +45 degree I signal phase shifter having an input coupled to said I signal mixer;
• wherein said Q signal path further comprises
• a Q signal path mixer having a first input coupled to said received RF signal and a second input coupled to said −45 degree LO phase shifter;
• and
• a −45 degree Q signal path phase shifter having an input coupled to said Q signal path mixer.

A single conversion method of converting a received RF signal into an IF output signal, said method comprising:

• splitting said received RF signal into separate I and Q signal components;
• phase shifting said I and Q signal components;
• summing said I and Q signal components to generate said IF output signal, wherein an image channel is substantially canceled from said IF output signal;
• measuring a phase error between said I and Q signal components, wherein said measuring said phase error further comprises injecting an injection test signal along with said receiving said RF signal;
• and
• adjusting the relative phase of said I and Q signal components to substantially remove said phase error.

A single conversion method of processing an RF signal comprising:

• receiving said RF signal comprising substantially all channels in an RF band;
• splitting said RF signal into an I signal component and a Q signal component, wherein said I signal component comprises an I selected channel and an I image channel, and wherein said Q signal component comprises a Q selected channel and a Q image channel;
• phase shifting said I and Q signal components;
• summing said phase shifted I and Q signal components to generate an IF output signal comprising said I and Q selected channels, wherein said I and Q image channels are substantially canceled from said IF output signal;
• and
• correcting for a phase error between said I signal component and said Q signal component wherein said correcting for said phase error further comprises injecting an injection test signal along with said receiving said RF signal.

A single conversion RF tuner for converting a received RF signal into an IF output signal, said tuner comprising:

• means for splitting said received RF signal into separate I and Q signal components;
• means for phase shifting said I and Q signal components;
• means for summing said I and Q signal components to generate said IF output signal, wherein an image channel is substantially canceled from said IF output signal;
• means for measuring a phase error between said I and Q signal components, wherein said means for measuring said phase error further comprises means for injecting an injection test signal along with said receiving said RF signal;
• and
• means for adjusting the relative phase of said I and Q signal components to substantially remove said phase error.