Patent ID: 8067987

Claim:
A voltage controlled oscillator-phase lock loop (VCO-PLL) system comprising: a voltage controlled oscillator (VCO) system comprising: a control circuit; a first cross-coupled oscillator system adapted to receive a source voltage, the first cross-coupled oscillator system comprising: a first transistor comprising a first source, a first gate, and a first drain, the first source coupled to the source voltage, the first gate coupled to the control circuit; a first inductor comprising a first end and a second end, the first end coupled to the first drain of the first transistor, and the second end coupled to a first node; a second inductor comprising a first end and a second end, the first end coupled to the first drain of the first transistor, and the second end coupled to a second node; a first varactor coupled between the first node and a first tuning voltage controlled by the control circuit; a second varactor coupled between the second node and the first tuning voltage controlled by the control circuit; a second transistor comprising a second source, a second gate, and a second drain, the second drain coupled to the first node, the second gate coupled the second node, and the second source coupled to a ground signal; and a third transistor comprising a third source, a third gate, and a third drain, the third drain coupled to the second node, the third gate coupled the first node, and the third source coupled to the ground signal; a second cross-coupled oscillator system adapted to receive the source voltage, the second cross-coupled oscillator system comprising: a fourth transistor comprising a fourth source, a fourth gate, and a fourth drain, the fourth source coupled to the source voltage, the fourth gate coupled to the control circuit; a third inductor comprising a first end and a second end, the first end coupled to the fourth drain of the fourth transistor, and the second end coupled to a third node; a fourth inductor comprising a first end and a second end, the first end coupled to the fourth drain of the fourth transistor, and the second end coupled to a fourth node; a third varactor coupled between the third node and a second tuning voltage controlled by the control circuit; a fourth varactor coupled between the fourth node and the second tuning voltage controlled by the control circuit; a fifth transistor comprising a fifth source, a fifth gate, and a fifth drain, the fifth drain coupled to the third node, the fifth gate coupled the fourth node, and the fifth source coupled to the ground signal; and a sixth transistor comprising a sixth source, a sixth gate, and a sixth drain, the sixth drain coupled to the fourth node, the sixth gate coupled the third node, and the sixth source coupled to the ground signal; and a phase-locked-loop (PLL) system; and a mixer system.