Abstract: A method for valuation of image dark data based on similarity hashing, the method including: (1) acquiring a dark dataset, and inputting the dark dataset into a trained deep self-taught hashing algorithm model to obtain a hash code of each image in the dark dataset; (2) constructing a hash map according to the hash code of each image in the dark dataset obtained in (1), where the hash map includes a plurality of nodes, each node represents the hash code of each image; (3) acquiring a significance score of each node in the hash map obtained in (2); and (4) sorting significance scores of the plurality of nodes obtained in (3) in a descending order, and outputting images corresponding to top k significance scores of the plurality of nodes to users, where k is a natural number.

Abstract: A method for valuation of image dark data based on similarity hashing, the method including: (1) acquiring a dark dataset, and inputting the dark dataset into a trained deep self-taught hashing algorithm model to obtain a hash code of each image in the dark dataset; (2) constructing a hash map according to the hash code of each image in the dark dataset obtained in (1), where the hash map includes a plurality of nodes, each node represents the hash code of each image; (3) acquiring a significance score of each node in the hash map obtained in (2); and (4) sorting significance scores of the plurality of nodes obtained in (3) in a descending order, and outputting images corresponding to top k significance scores of the plurality of nodes to users, where k is a natural number.

Abstract: Methods and systems for I/Q mismatch calibration and compensation for wideband communication receivers may include receiving a radio frequency (RF) signal in a receiver of a communication device, down-sampling the received RF signal to generate a channel k and its image channel ?k at baseband frequencies, and determining average in-phase (I) and quadrature (Q) gain and phase mismatch of the channel k and the image channel ?k. A curvature of gain mismatch for the channel k and the image channel ?k may be estimate utilizing a blind source separation (BSS) estimation algorithm. The average I and Q gain and phase mismatch of the channel k and the image channel ?k may be removed. A residual phase tilt and a residual amplitude tilt of the channel k and the image channel ?k (with removed average I and Q gain and phase mismatch) may be determined.

Abstract: Methods and systems for I/Q mismatch calibration and compensation for wideband communication receivers may include receiving a radio frequency (RF) signal in a receiver of a communication device, down-sampling the received RF signal to generate a channel k and its image channel ?k at baseband frequencies, and determining average in-phase (I) and quadrature (Q) gain and phase mismatch of the channel k and the image channel ?k. A curvature of gain mismatch for the channel k and the image channel ?k may be estimate utilizing a blind source separation (BSS) estimation algorithm. The average I and Q gain and phase mismatch of the channel k and the image channel ?k may be removed. A residual phase tilt and a residual amplitude tilt of the channel k and the image channel ?k (with removed average I and Q gain and phase mismatch) may be determined.