A joint design method of frame synchronization code and LDPC code

Frame synchronization word (FSW) is an important basis in signal synchronization detection. In our work, the joint design of frame synchronization words and error correcting code are proposed which through regularly distributing the frame synchronization words among the information bits to improve the decoding performance of the LDPC. Frame synchronization word should be added to the information sequence corresponding to the position with the check matrix larger column weight which can guarantee that more Frame synchronization words are received by the check node in the decoding iteration. The frame synchronization word is known to the receiver which play an important role in decoding iteration. The results of simulation show that the algorithm makes an obvious improvement in decoding performance when the signal-noise ratio (SNR) is lower than 1 dB

Hydrogel with dual networks making reduced GO connection and orientation for a bi-directional thermal conductive film

With the rapid development of modern electronic devices, materials having high thermal conductivities (TCs) both in in-plane and through-plane directions are specially needed for thermal management. Whereas, the construction of efficient thermal-conductive pathways in bi-directions is still a challenge. Herein, a facile gel-drying approach is developed, achieving the formation of bi-directional pathways with the assistance of a dual-network structure. During the process, cellulose nanocrystal (CNC) with a high intrinsic TC was mixed with gellable cellulose (CNF) to form CNF/2CNC dispersion which was then used as a matrix. Reduced graphene oxide (RGO) foam with a network structure was used as a filler. The RGO network was tightly wrapped by the formed CNF/2CNC cross-linking network, resulting in a hydrogel with a dual-network structure. After drying, the resultant RGO-foam-CNF/2CNC film not only has a long-range orientation path in the horizontal direction, but also maintained a connected path in the vertical direction. The resultant film with 18.5 wt% RGO exhibited high TCs of 14.06 W·m−1·K−1 and 2.47 W·m−1·K−1 simultaneous for in-plane and through-plane directions, which is 21.6 times and 9.88 times higher than those of a typical CNF film, respectively. This strategy offers a new avenue for the designs of soft, cuttable, environmentally friendly polymer composite films with high TCs in bi-directions