Information Technology Reference
In-Depth Information
To date, the wireless multimedia study has focused on robust video trans-
mission over general PS wireless channels. There is, however, a scarcity of
work performed on delivering data from a 3G CS wireless network or system
to other PS networks. The key issue for data delivery over a 3G network, which
consists of several layers, is that it is not obvious how to achieve end-to-end
optimality for data delivery although a single-layer performance can reach
optimum. Aiming to solve such a problem, we present a new architecture,
which leads to interoperability between the sensor and UMTS networks to
move the video from a sensor to a user at a lower cost and lower power.
As pointed out above, this chapter works on UMTS networks and PSN
networks from the following three aspects:
1. For the UMTS networks, we will present an efficient implementation
of 3G-324M protocol stack for low bit rate multimedia communication,
control and data multiplexing protocols H.245 and H.223, targeted for
a multipoint video user in both 3G and wireless local area network
(WLAN) environments. We will present the design and implemen-
tation details of an efficient and robust multimedia gateway that
enables ubiquitous multimedia wireless communication. To achieve
the performance improvement of the gateway, we focus on efficiently
implementing the H.245, which is the main call handling and signal-
ing protocol. In our method, sets of H.245 messages are compiled,
used, and stored in a table so as to be reused for further incoming
calls. After implementing this procedure, we have successfully tested
our 3G-IP gateway, which is robust enough for smoothly handling up
to one million concurrent calls.
2. For the PSN networks, we contribute to the effort by introducing a
new architecture for video transmission from a sensor to the UMTS
terminal at a low cost and power for the purpose that the video sen-
sors can be within reach of UMTS for best utilization of UMTS cover-
age. The integration of the mobile network infrastructure and sensor
ad hoc networks can reduce the cost of building new infrastructure
and enable the large scale deployment of sensor networks. Further
more, we build up the platform and implement the video gateway.
The advantages are that communicating between these two systems
dynamically and intelligently can reduce the cost and increase the
lifetime of sensor networks. It was also shown that this approach is
suitable for all organizations and for gathering data on demand. The
feasibility and viability of the proposed method has been proven
through initial experimental work.
3. For video quality measurements and predictions, we present the
video quality measurements and predictions for low bit rate video
during our real implementation work. Toward this, the Perceptual
Evaluation of Video Quality (PEVQ) is introduced and exploited
