Compared with the force-to-rebalance mode, the whole angle mode of the hemispherical resonator gyro has the advantages of large measurement range and high linearity. In order to address the problems that the accuracy loss during the calculation of standing wave azimuth angle in the existing whole angle mode demodulation scheme and the sensitivity of the output to temperature change, based on the principle of linear superposition of traveling waves, the paper proposes a standing wave information solution method of hemispherical resonator gyro based on clockwise and counterclockwise traveling wave synchronous frequency demodulation. A multi-loop control method based on frequency demodulation for whole angle mode hemispherical resonator gyro is designed to achieve frequency, amplitude, and orthogonal control of standing waves. In response to the difficulties in optimizing FPGA circuit algorithms and low floating-point accuracy, a “FPGA+DSP” dual core hemispherical resonator gyro digital control circuit is designed and implemented. The effectiveness of the control scheme and digital control circuit proposed in this paper is verified through physical experiments. The experimental results show that this scheme can reduce the influence of resonant frequency changes caused by temperature fluctuations on the output of the gyroscope.