What will come out if you mix femtocell, picocell, metrocell, macrocell, Wi-Fi, cloud RAN and Distributed Antenna Systems (DAS)? Wait, there is more to layer on top of this – 2G, 2.5G, 3G, LTE and LTE Advanced. Well, you guessed right – the Heterogeneous Network (a.k.a. the HetNet) is born.
Late last year, I had the pleasure of attending two back-to-back conferences in sunny San Diego, Femtocell Americas and HetNet, both of which featured discussions on this new type of network.
As the names implies, HetNet by definition means disparate networks. If we start to dig deeper, we may find that HetNet is not just the coexistence of different cell sizes or different access technologies or even different network architectures. HetNet is about providing a seamless experience to consumers by the effective usage of technology tools such as Multiple Input Multiple Output (MIMO), Self Organizing Networks (SON), Interference Management, Spectral efficiency, Bandwidth management, Inter RAT mobility, unified security across all accesses, Local IP offload (LIPA) and many more.
The HetNet is the vendor community’s response to the “iPhenomenon,” which has fundamentally changed wireless networks forever. Blame it on the simplicity of using today’s smart devices, but it is a realization by operators and wireless infrastructure providers that the onus of counterbalancing the simplicity of devices now lays on their shoulders.
Once a famous scientist named TenTeh (I just made this up, its HetNet backwards) laid out two simple principles–
- The complexity of wireless network will be inversely proportional to the ease of user experience; and
- The total sum of complexity in the wireless network will always remain constant.
In last five years or so, handheld devices have evolved to be as simple as possible. Both my three year old kid and my 75 years old grandma can use a smartphone with equal ease and when they are not using it I respond to emails, write and post a blog and can then check how many of my friends like it (too bad there’s no unlike button).
This simplicity and multiple usages of smart devices have prompted – A) Increased complexity of wireless networks (TenTeh’s first principle) and B) Rebalancing of the complexity in the wireless networks (TenTeh’s 2nd principle).
Who’s getting burdened by all this? It’s the infrastructure network.
Guess what, HetNet is just a complexity phenomenon started at the access but slowly it is penetrating into the edge gateways as well. Tomorrow’s gateway will also have to burden their fair share of complexity. Gateways need to be intelligent, adaptive and fast to tackle what HetNets are going to throw at them. More on Gateways in my next blog.
At the end of the day, I am relaxed to know that there is a whole community out there, including my own company, Radisys, who is working very hard to solve capacity and coverage issues created by uses like me. You can check out our award-winning Trillium products here to learn more about how we partner with our customers to solve these very issues.