Several Key Problems In Future Urban Road Broadband Hybrid Networks

Multimedia communication in urban road circumstances is important, but at the same time, so complicated to realize that there is still much further work to be done.Several promising technologies had been analysed and compared before a hybrid network frame oriented to future urban road multimeadia services was proposed, as a starting point to address three tasks listed below.1. As to the intelligent selection in hybrid wireless access networks, a utility based network selection scheme was proposed. Different from a traditional method only considering two factors, our scheme took much more facors important for multimedia application into account within a simple framework. A rudimental simulator was also developed.2. As to the ONU(Optical Network Unit)s'optimal placement, a scheme to characterize urban road features based on traffic flow was presented, considering traffic flow as a key factor under this scenario. Furthermore, four examined spot types were defined and two placement evaluation strategy were proposed. The scheme can be utilized to migrate some existing optimal ONU placement methods to urban road circumstance.3. As to noise-resistance feature of wireless video, a new unequal error protection method was given, which considered both the impact of error propagation from the previous frame and that to the following frames. Experimental results showed that our method presented quality improvement when compared with the conventional one.