exterior quality
7.For improving transmission quality of physics channel in NLOS BWA operation environment and solving multi-path and frequency selectivity attenuation in city wireless complex channel environment,the OFDM-based OFDMA BWA and OFDMA modulation specialty are discussed in this paper,and the exterior environment,capacity and problems of BWA and the service strategy for improving quality of NLOS BWA are analyzed also.
8.By adoption of a series of construction techniques, such as Doka sheathing board pasted with Finland board, affixing double-sided gum at the bottom of the sheathing board, controlling depot exterior with angle steel, and mending fissures with epoxy resin putty, the quality of as-cast-finish concrete can meet the requirement of construction anti good technical effect can be achieved.
10.According to the optical image theory, this paper analyzes the principle of the self-focusing lens and introduces the type and characteristics of the self-focusing lens array (SLA). The present article also discusses the calculation method of optical parameter and exterior size for the self-focusing lens and the measurement method of the image quality for the SLA. The last part of the paper analyzes and indicates the acceptable errors of the SLA of xerox machine design and assembling adjustment.
