Episode 4 of 6: Evolution of Multi-Carrier DAS
Even the most advanced DAS systems in the market are not capable of meeting the network capacity and flexibility demands coming our way. Frankly, there have not been many ground breaking innovations from DAS manufacturers over the last five years. While there have been some novel concepts with novel benefits, nothing has really changed the playing field.
While our multi-carrier DAS platform represents our effort at improving existing technologies by adding fiber-saving wave division multiplexing (WDM), surface acoustic wave (SAW) filtering and intuitive DAS management software to mainstream architecture, in an analog world, there is only so much you can do within the constraint of physics. Manufacturers have instead focused on developing a broader range of products (1 watt, 5 watts and 20 watts) that may include single-carrier DAS, multi-carrier DAS and high-power/outdoor DAS.
Building owners and wireless service providers are using what is available in the market today while pining for the more efficient and more flexible architectures of the future. Meanwhile, each of the major DAS vendors is hard at work planning next-generation digital and/or IP solutions while trying to figure out how to integrate a variety of network elements. Whether delivered over a fiber, coax or CAT6 cable, the distribution of RF energy using amplifiers close to end-users is the very essence of small-cell network philosophy.
These small-cell networks (sometimes being called “heterogeneous networks” or het-net) are a coming vision of one network extending from the core to the base station to the outdoor DAS to the indoor DAS to the femto cell with seamless hand-offs. RF power levels are stepped-down as the transceiver elements gets closer to the handset and move into areas where towers simply aren’t allowed. Sometime soon unused capacity at a cell site in the suburbs will be digitally routed to a venue in the inner city where it will drive a remote radio head that feeds a DAS. As technologies, like the digital wavelength-division-multiplexed passive optical network (DWDM-PON) laser take hold in the market delivering data speeds at 16 to 32 Gbps, digital transport costs will drop and create opportunities to harvest unused capacity for use where it is needed most.
True next-generation DAS solutions will have the following characteristics;
1) Efficient spectrum utilization through dynamic capacity routing
2) The ability to grow throughput to support gigabit devices
3) Delivery of a shared high-speed backbone for GBe, Sonet, and CPRI networks
4) Improved RF performance by reducing system noise and controlling system delay
5) Monitoring and management of traffic for all services
Clearly, myriad details need to be worked through as an industry. However, there seems to be broad consensus that the DAS architectures developed over the next decade will look very different from what we deploy today.
This article was originally published on AGL Bulletin.