iWireless Solutions recently responded to Ofcom’s consultation regarding improving spectrum access for consumers in the 5 GHz band. We thought we would share our response with you, and we hope it gives you some insight into our thinking and approach to the subject.
iWireless Solutions Ltd Response to Ofcom’s Consultation “Improving spectrum access for consumers in the 5 GHz band”
iWireless Solutions Ltd welcomes the opportunity to respond to Ofcom’s consultation “Improving spectrum access for consumers in the 5 GHz band”.
iWireless Solutions Ltd (iWireless) is a leading wireless systems integrator. We provide wireless consultancy, audit, design, installation and maintenance services for Wi-Fi, Cellular and other wireless technologies. iWireless provides solutions in complex environments with high user densities such as stadia, airports and urban areas.
Many of our customers are heavily dependent on the 5 GHz band, mostly for Wi-Fi but also for fixed wireless access (FWA). Wi-Fi congestion is becoming an issue as demand increases, as well as interference from other Wi-Fi systems outside our customers’ demises. Licence-exempt spectrum is a valuable but limited resource and needs careful coordination where possible to maximise the benefit. iWireless is supportive of attempts by Ofcom to increase the amount of spectrum for Wi-Fi, subject to a full analysis of the impact on other services such as FWA.
Answers to the specific questions in the consultation document are given below.
Question 1: Do you agree with our proposal to prioritise consideration of the 5725-5850 MHz frequencies for Wi-Fi, subject to appropriate protections to other users, in particular satellite services?
Yes, given that Ofcom is able to make changes to this sub-band without international agreement. The assessment of coexistence should include all the other services listed in this consultation document and take account of potential future usage. In particular, outdoor Wi-Fi may depend on the availability of reliable FWA backhaul in the 5.8 GHz band.
We note that there are over 10,000 registered FWA terminals in this band. We believe Ofcom should allow public access to this database, for example by adding terminal locations to Ofcom’s Sitefinder service, so that users can make informed decisions on the suitability of this band for FWA in specific locations.
Ofcom should also consider the use of Total Radiated Power (TRP) constraints instead of, or as well as, maximum EIRP constraints, as TRP is often a better measure of spectrum resource usage. This might allow the use of higher gain antennas for FWA to mitigate the impact of co-channel Wi-Fi.
Question 2: Do you agree with our proposal to re-examine the requirement for DFS across the 5 GHz band, subject to appropriate protections to other users?
Yes. We believe revised DFS constraints could be particularly beneficial indoors, where Cellular is not always available and where walls limit the impact of Wi-Fi on radars. DFS causes significant disruption to 802.11ac services using bonded channels. Ofcom should also consider possible measures by regulators and vendors to ensure Wi-Fi usage does not end up concentrated in the non-DFS channels.
Question 3: Do you think we should pursue the other options we have identified: opening up 5850-5925 MHz; outdoor Wi-Fi use at 5150-5350 MHz; and opening up the ‘centre gap’ at 5350-5470?
Yes, iWireless is supportive of opening up 5850-5925 MHz and 5350-5470 MHz to Wi-Fi, as we believe Wi-Fi usage would generate significant economic benefit compared to other potential uses of this spectrum.
iWireless is also supportive of allowing outdoor use of Wi-Fi at 5150-5350 MHz to meet increasing demand in urban areas such as central London. However, we believe allowing higher power levels in this band needs careful consideration as it may cause more interference in uncoordinated environments such as outdoors. What is the experience of USA and Japan with higher powers in e.g. dense urban environments?
Question 4: What are your views on the future growth in demand for Wi-Fi? In which use scenarios do you expect to see the greatest pressure for delivery of high-quality Wi-Fi access? What evidence do you have to support your views?
iWireless believes the demand for Wi-Fi and 5 GHz spectrum will continue to grow as users consume more data on mobile devices, and operators develop Wi-Fi Calling, Wi-Fi Offload, LAA and MulteFire services in the same spectrum.
We believe the greatest pressure on Wi-Fi services will be in multi-tenant indoor environments without Wi-Fi coordination such as shopping centres, and where some of the required services are business critical, e.g. wireless point of sale (POS).
Question 5: Do you think technology improvements and densification of access points will be sufficient to meet demand or will there also be a need for more spectrum beyond that which we propose to make available? What evidence do you have to link between demand for data and demand for additional spectrum?
We agree with Ofcom’s analysis that densification can increase Wi-Fi capacity in coordinated environments, but will have limited success where spectrum usage is not coordinated. Individual retailers etc. will tend to use maximum permitted power to guarantee their own connectivity, to the detriment of other users. The relaxation of power limits would further limit the benefits of densification. However, landlords in multi-tenant buildings should be able to coordinate Wi-Fi usage and maximise capacity.
Question 6: What real life speed and quality of experience can consumers expect in practice from devices using the 5GHz spectrum as authorised in the UK now? What changes can we expect as the number of devices increases and technology improves? What difference in speeds and quality of experience would additional spectrum make?
Modern devices are able to handle high bandwidth connectivity. The major constraint is limited spectrum, as well as limited backhaul in some cases. Additional Wi-Fi spectrum and flexibility in its usage would help satisfy increasing demand, subject to appropriate power limits.
Question 7: How important is contiguous spectrum? How wide should channels be to support future demand?
Wideband channels require contiguous spectrum, hence DFS events are highly disruptive to high bandwidth communications.
Question 8: Do you believe we have correctly identified the incumbent services in 5150-5925 MHz which need to be taken into account in considering opening up more 5 GHz Improving access to 5 GHz band spectrum for Wi-Fi? Are there any other services which will need to be taken into account in future studies?
iWireless is not aware of any other incumbent services in this band.
Question 9: What coexistence studies, measurement campaigns and mitigation techniques do you believe would be most effective for demonstrating coexistence between Wi-Fi and incumbent users?
iWireless would like to see further work undertaken on the coexistence of Wi-Fi and FWA.
Question 10: Do you intend to participate and provide technical material into the ITU and CEPT work? In what way?
iWireless has no plans at present to participate directly in this work.
If you would like to learn more about iWireless Solutions’ perspective on this please feel to contact us and speak to Mike Kennett, our Wireless Consultant.