We study the transmission capacities of two coexisting spread-spectrum wireless networks (a primary network vs. a secondary network) that operate in the same geographic region and share the same spectrum. We defi ne t...We study the transmission capacities of two coexisting spread-spectrum wireless networks (a primary network vs. a secondary network) that operate in the same geographic region and share the same spectrum. We defi ne transmission capacity as the product among the density of transmissions, the transmission rate, and the successful transmission probability. The primary (PR) network has a higher priority to access the spectrum without particular considerations for the secondary (SR) network, while the SR network limits its interference to the PR network by carefully controlling the density ofits transmitters. Considering two types of spread-spectrum transmission schemes (FH-CDMA and DS-CDMA) and the channel inversion power control mechanism, we quantify the transmission capacities for these two networks based on asymptotic analysis. Our results show that if the PR network permits a small increase ofits outage probability, the sum transmission capacities of the two networks (i.e., the overall spectrumefficiency per unit area) will be boosted significantly over that of a single network.展开更多
Micro-film is a product from the development of mobile media technology based on the network media, and the short and typical screen expression ability and effect are its forms of contents. Different from the communic...Micro-film is a product from the development of mobile media technology based on the network media, and the short and typical screen expression ability and effect are its forms of contents. Different from the communication way of traditional advertising, micro-film advertising has the characteristics of both social networking and video communication. With the creative characteristics of micro-film advertising, the conamunication way of video advertising has been started. In this paper, through the introduction to the advantages of micro-film advertising communication and combining with the development of micro-film in the new period, the application of aesthetic ideas to micro-film advertising is further explored, and then the striking expression effect caused by micro-film advertising is introduced.展开更多
基金supported in part by the China 863 Program grants 2007AA10Z235, 2007AA01Z179, 2006BAJ09B05, 2008BADA0B05the NSFC grants 60972073, 60871042, 60872049, and 60971082+1 种基金the China National Great Science Specifi c Project grant 2009ZX03003-011the China 973 Program grant 2009CB320407
文摘We study the transmission capacities of two coexisting spread-spectrum wireless networks (a primary network vs. a secondary network) that operate in the same geographic region and share the same spectrum. We defi ne transmission capacity as the product among the density of transmissions, the transmission rate, and the successful transmission probability. The primary (PR) network has a higher priority to access the spectrum without particular considerations for the secondary (SR) network, while the SR network limits its interference to the PR network by carefully controlling the density ofits transmitters. Considering two types of spread-spectrum transmission schemes (FH-CDMA and DS-CDMA) and the channel inversion power control mechanism, we quantify the transmission capacities for these two networks based on asymptotic analysis. Our results show that if the PR network permits a small increase ofits outage probability, the sum transmission capacities of the two networks (i.e., the overall spectrumefficiency per unit area) will be boosted significantly over that of a single network.
文摘Micro-film is a product from the development of mobile media technology based on the network media, and the short and typical screen expression ability and effect are its forms of contents. Different from the communication way of traditional advertising, micro-film advertising has the characteristics of both social networking and video communication. With the creative characteristics of micro-film advertising, the conamunication way of video advertising has been started. In this paper, through the introduction to the advantages of micro-film advertising communication and combining with the development of micro-film in the new period, the application of aesthetic ideas to micro-film advertising is further explored, and then the striking expression effect caused by micro-film advertising is introduced.
