Explosive consumer demand for mobile Internet and Cloud-based content throughout Asia has created widespread data bottlenecks, bandwidth shortages, and excessive data charges over terrestrial 4G/LTE mobile networks. The one-to-one unicast architecture of mobile networks is not designed for the highly asymmetric nature of consumer demand for video today, where 5% of Internet content typically accountsfor 80% of all downloads. Exacerbating the congestion is the linear-limited growth of cellular networks, which can only expand by getting more spectrum, building more cell sites, and waiting for more technological breakthroughs. When faced with the potentially thousand-fold increase in data traffic in the next 10 years, and the fact that billions of people in remote regions remain unconnected, this problem will need a new structural delivery solution.
Asymmetric consumption of content, illustrated
One-to-one unicast architecture
The cellular networks of today are optimized for unicasting services (i.e., link-based one-to-one communications) and thus are inherently disadvantageous in massive contents delivery, especially in vehicle applications with stringent demands on volume capacity, cost effectiveness, ubiquitous coverage, and consistent quality of services (QoS). Given the exponential growth in mobile traffic, it is well established that the mobile bottleneck problem cannot be coped with using cellular infrastructure expansion alone – an entirely different network architecture must be introduced in order to exploit the unique characteristics of mobile multimedia contents.
Built upon the above principles and its past success in CMMB terrestrial broadcasting technologies, our team has developed the world’s first truly converged satellite-terrestrial & broadcast-unicast convergent network which can provide order-of-magnitude performance benefits in terms of system capacity, cost, and coverage for the mobile multimedia markets. Specifically, our solution involves a powerful L-band mobile broadcast satellite, Silkwave-1, that delivers nearly 100 Mbps of multimedia contents to an unlimited number of vehicle users over vast areas. Relative to existing network solutions, the CMMB satellite-terrestrial network is not only superior in data rate, coverage, and cost effectiveness, but also advantageous in service flexibility and the richness of its ecosystem.
While the 2G network in China covers about 99% of the population, the 3G and 4G networks that carry the majority of mobile data traffic cover only 73% and 20% of the population respectively. 2G coverage is well rolled out in the populated regions of the country, with coverage of all 31 provinces and autonomous regions. Western regions with small and concentrated habitations limit the need for full geographic coverage. The 3G network has coverage of all county level towns, while 4G rollout has so far only been focused on top-tier cities. This means there are significant coverage black spots in other areas where 27% of the population does not have access to high quality mobile data services.
Given the data and user growth described above, traditional network operators have three key choices: increase their spectrum, increase the efficiency of existing transmitters and equipment, or increase their number of transmitters.
In China, availability of additional spectrum is extremely scarce and furthermore comes at a great cost, so is not a viable option for mobile network operators. Furthermore, the absolute amount of spectrum is limited, hence this is not a long-term solution.
Boosting the efficiency of existing equipment (e.g. the move from 3G to LTE) is the most efficient way to enhance their networks, but is costly. Furthermore, owing to continuous upgrade cycles, this has a high probability of lowering returns, as good but lower capacity equipment is retired before it reaches the end of its economic life.
Operators have been significantly boosting their number of transmitting towers to increase capacity and reach. However, this increase has not kept pace with increases in subscriber numbers. As a result, the number of 3G subscribers per Base Transceiver Station (BTS) has increased almost four-fold in the past five years. Bandwidth is thus shared across a larger user base, leading to a deteriorating user experience.