US Patent No. 9,423,496

WIRELESS DETECTION DEVICES AND WIRELESS DETECTION METHODS


Patent No. 9,423,496
Issue Date August 23, 2016
Title Wireless Detection Devices And Wireless Detection Methods
Inventorship Tzyy-Sheng Horng, Kaohsiung (TW)
Fu-Kang Wang, Kaohsiung (TW)
Kang-Chun Peng, Kaohsiung (TW)
Assignee NATIONAL SUN YAT-SEN UNIVERSITY, Kaohsiung (TW)

Claim of US Patent No. 9,423,496

1. A wireless detection device, comprising:
a voltage control oscillation unit, generating a plurality of oscillation signals with different frequencies according to
analog control voltages;

a transceiving unit, outputting a plurality of first wireless signals to an object in a predetermined area according to the
oscillation signals, and receiving second wireless signals generated by reflection of the first wireless signals to yield
self-injection-locking signals for modulating the voltage control oscillation unit;

a demodulation unit, configured to demodulate the oscillation signals into first voltage signals;
a signal generating unit, configured to generate the analog control voltages; and
a processing unit, subtracting the corresponding analog control voltages from the first voltage signals to generate second
voltage signals,

wherein when the variation of the second voltage signals in frequency domain exceeds a predetermined value on a target frequency,
the processing unit calculates a distance between the object and the transceiving unit and further a variation frequency of
the distance according to the target frequency, wherein the processing unit further comprises:

a first subtractor, connected to the signal generating unit and the demodulation unit, and configured to subtract the corresponding
analog control voltages from the first voltage signals to generate the second voltage signals;

a first calculating unit, connected to the first subtractor, and configured to transform the second voltage signals into frequency
domain;

a storage unit, configured to store spectra of the transformed frequency domain of the second voltage signals at different
times;

a second subtractor, connected to the storage unit, and configured to obtain a difference between the spectra of the second
voltage signals; and

a second calculating unit, connected to the storage unit, and configured to transform the time-varying spectra into the variation
frequency of the distance.