This paper study the transmission capacity of wireless sensor networks based on the cooperative diversity technology. At first, the paper establish the cooperative diversity model for multi-source, multi-sink and multi-relay sensor networks, on which the specific transmission capacity expression of wireless sensor networks is deduced, it not only prove that the transmission capacity of wireless sensor networks will be increased by the cooperative diversity technology, but also give the criterion for discussing further the application effect of the technical scheme such as the cooperative selection strategy and so on in actual wireless sensor networks. In the other hand, the paper theoretically prove that cooperative diversity can improve the transmission capacity of wireless sensor networks. At last, some simulations are given and validity of the results is testified by the simulations.
