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Distributed compressive video sensing (DCVS) is a new emerging video codec that incorporates advantages of distributed video coding (DVC) and compressive sensing (CS). However, due to the absence of a good sparse basis, the DCVS does not achieve ideal compressing efficiency compared with the traditional video codec, such as MPEG-4, H.264, etc. This paper proposes a new hybrid sparse basis, which combines the image-block prediction and DCT basis. Adaptive block-based prediction is employed to learn block-prediction basis by exploiting temporal correlation among successive frames. Based on linear DCT basis and predicted basis, the hybrid sparse basis can achieve sparser representation with lower complexity. The experiment results indicate that the proposal outperforms the state-of-the-art DCVS schemes on both visual quality and average PSNR. In addition, an iterative fashion proposed in the decoder can enhance the sparsity of the hybrid sparse basis and improve the rate-distortion performance significantly.

The spin-exchange relaxation-free (SERF) atomic magnetometer is one of the ultra-sensitive magnetometers, which must be operated in a low magnetic field and heated more than 100°C. One of the main engineering difficulties in fabricating a SERF atomic magnetometer is to develop a heater that introduces no additional magnetic noise into the measurement system. In this paper, a novel compact current-heating scheme and apparatus for the SERF atomic magnetometer are proposed. The thermal and magnetic simulations of this apparatus are carried out and the results of the simulations demonstrate the feasibility of this heating apparatus: the vapor cell can be heated to a temperature of 103°C and magnetic field introduced in the magnetometer can be limited in 10nT.

We are developing a new detection scheme for magnetometers based on atomic vapor confined in millimeter-scale micromachined enclosures and atomic Zeeman transitions. By adding three micro-reflective mirrors and modifying the light path arrangement, the new detection scheme effectively hurdles the main obstacle which prevents SERF from being applied in chip scale sensors, i.e. the difficulty to implement the transverse laser fields using MEMS fabrication methods. Instead of guiding the pumping laser beam parallel to the wafer plates that is not compatible with MEMS fabrication, such scheme rotates both pumping and probing laser beams, and maintains the orthogonal relationship between them. Finally, several fabrication process suited for this scheme are discussed.