Abstract: A bidirectional reflectance distribution function (BRDF) measurement system and method, an electronic device, and a storage medium. The BRDF measurement system includes: a blackbody, a spectroradiometer and a controller; where in case that the blackbody is heated to a target temperature, it undergoes a solid-liquid phase change; the spectroradiometer is used to measure the blackbody and transmit a first measurement signal to the controller, and in case that the blackbody irradiates a to-be-measured point on a sample surface, the spectroradiometer is further used to measure radiation from the to-be-measured point, and transmit a second measurement signal to the controller; and the controller is used to obtain a BRDF of the to-be-measured point based on the first measurement signal, the second measurement signal, the target geometric relationship, a target mapping relationship and a dimension parameter of the blackbody.

Abstract: A SiC ohmic contact preparation method is provided and includes: selecting a SiC substrate; preparing a graphene/SiC structure by forming a graphene on a Si-face of the SiC substrate; depositing an Au film on the graphene of the graphene/SiC structure; forming a first transfer electrode pattern on the Au film by a first photolithography; etching the Au film uncovered by the first transfer electrode pattern through a wet etching; etching the graphene uncovered by the Au film through a plasma etching after the wet etching; forming a second transfer electrode pattern on the SiC substrate by a second photolithography; depositing an Au material on the Au film exposed by the second transfer electrode pattern and forming an Au electrode and then annealing. The graphene reduces potential barrier associated with the SiC interface, specific contact resistance of ohmic contact reaches the order of 10?7˜10?8 ?·cm2, and the method has high repeatability.

Abstract: The present invention provides a method of power control for a plurality of secondary users (SUs), or unlicensed users, in a cognitive radio network having a plurality of primary users (PUs), or licensed users. The method comprises determining an optimal power level for each of the SUs such that a total throughput of all the SUs is maximized while satisfying an individual throughput requirement of each SU and an interference limit constraint of the PUs. In particular, a case having two SUs is considered.

Abstract: The present invention provides a method of power control for a plurality of secondary users (SUs), or unlicensed users, in a cognitive radio network having a plurality of primary users (PUs), or licensed users. The method comprises determining an optimal power level for each of the SUs such that a total throughput of all the SUs is maximized while satisfying an individual throughput requirement of each SU and an interference limit constraint of the PUs. In particular, a case having two SUs is considered.