Patent ID: 7952443

Claim:
An assistant measuring circuit for an oscillator providing 8 oscillating signals with 8 different phases of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, the assistant measuring circuit comprising: 8 buffers, an ith buffer among the 8 buffers being electrically connected to the oscillator, the ith buffer receiving and further transmitting an ith oscillating signal among the 8 oscillating signals, i being an integer between 1 and 8; 8 reflection-type modulators, an ith modulator among the 8 modulators being electrically connected to the ith buffer and having an ith signal input end, an ith signal output end, and an ith signal control end, the ith oscillating signal being transmitted to the ith signal input end through the ith buffer, and all the signal output ends of the 8 modulators being electrically connected to a measuring end; and a controller, electrically connected to each of the ith signal control ends, for providing an ith control signal to each of the ith signal control ends so as to close the reflection-type modulators for the 45°, the 135°, the 225°, and the 315° signals and to delay the 0° and 270° signals by 90° and the 90° and 180° signals by 270° to obtain two sets of quadrature signals or to close the reflection-type modulators for the 0°, the 90°, the 180°, and the 270° signals or to close the reflection-type modulators for the 90°, the 135°, the 270°, and the 315° signals.