We have covered Spectrum bridge before (An analysis of early white space network success stories and their future implications ..) and at that time, I wanted to write a follow on blog on their MWC demo.
White space networks are of interest to me both intellectually and also from a PhD perspective and in this post, I wanted to explore the wider implications of ‘spectrum harvesting’ on the industry.
I see white space technologies as ‘incrementally disruptive’ – i.e. just like Wi-Fi – they will be used by all industry players. White space networks also have some immediate use cases: Rural broadband, Machine to Machine and alleviating the spectrum crunch. ‘Spectrum harvesting’ relates to the ‘spectrum crunch’ aspect of white space i.e. the last element
The question is: will spectrum harvesting become the norm in future?
The basic announcement from spectrum bridge and Interdigital at MWC was: InterDigital to Collaborate with Spectrum Bridge on Spectrum Harvesting Technologies
Essentially, InterDigital and Spectrum Bridge collaborate to develop Dynamic Spectrum Management technologies that intelligently harvest TV White Space (TVWS) and other under-utilized frequency bands. Spectrum harvesting opens new blocks of radio waves for use by Wi-Fi®, LTE, and other wireless systems, addressing the ever-growing demand for wireless bandwidth.
Spectrum Bridge is a pioneer in white space databases (pdf) and the InterDigital Dynamic Spectrum Management solution uses this white space database for ‘spectrum harvesting’ – in practise, that means:
• Allocation and aggregation of contiguous and non-contiguous frequency channels across licensed, unlicensed and TV White Space;
• Database and sensing-assisted spectrum allocation;
• Extension of legacy systems such as Wi-Fi® and cellular into under-utilized frequency bands.
The interdigital announcement talks of a ‘network of networks’ : “The interdigital press release says: “that enable a network of networks to operate on underutilized frequencies, including TV whitespace (TVWS). Wi-Fi®, LTE, and other wireless systems can use this ground-breaking technology to harvest additional spectrum to service more users, increase data throughput, avoid interference, and build out the small cell, heterogeneous network that is now being recognized as the future of wireless
But how does this work?
Have a look at this video
At 0.55 mins, ‘available channels’ means all types of channels (LTE, white space, Wi-Fi)
This is truly disruptive – i.e. channels of network types are accessed transparently.
The final question is: What does White Space add to Wi-Fi?
a) First more bandwidth. Whatever spectrum you have at 2.4 and 5GHz now you add multiples of 6-8Mhz of UHF spectrum.
b) Also, propagation. White Space signals carry further so Wi-Fi range is extended and where a weak signal would mean low bandwidth you would now get more bandwidth.
The concepts are pervasive i.e. in the home, at a venue etc – if spectrum is seen not as ‘spectrum types’ (LTE, Wi-Fi, White space etc) – but rather holistically as ‘channels’ which may be ‘harvested’ by a service – that is truly interesting. I believe it could be the norm.