Showing posts with label Spectrum. Show all posts
Showing posts with label Spectrum. Show all posts

Wednesday 28 March 2012

Platinum Band: Sub 1GHz Frequency Band


Was listening to the Softbank webcast earlier about why they are so happy on receiving the 900MHz spectrum. The extract from slidepack summarises the advantages on this 'Platinum Band'

Monday 12 March 2012

Problems with 800MHz in UK and Spectrum to be auctioned


Even though 800MHz provides far better coverage than 2.1GHz (as shown above), it is going to be difficult to rollout LTE on 800MHz in the short term. The main reason being that there are quite a few other devices that use the frequencies or the frequencies neighbouring the 800MHz band and the interference may stop them working. A chart of the users is shown below.


It would be interesting to see when the rollouts in 800MHz would happen.

According to Ofcom, the following spectrum will be available in the UK:


• 250MHz of spectrum:
    • 2x30MHz paired at 800MHz
    • 2x70MHz paired at 2.6GHz
    • 50MHz unpaired at 2.6GHz
• (Also 2x15MHz of 1800MHz spectrum to be divested by EE)
• Starts to become available from Jan 2013
    • 800MHz expected to be available across whole of the UK by end of 2013
    • 2.6GHz across majority of UK by end of 2013 with remaining areas asap thereafter



All these topics were recently covered in a Cambridge Wireless event on Mobile Broadband SIG: Mobile Broadband in Rural Areas. The presentations are available here to view and download.

Tuesday 8 November 2011

Devices may require support for over 40 RF Bands to be used universally


Interesting picture from Qualcomm presentation in 4G World that shows that for Universal use, a device may have to support over 40 RF bands (which may not be physically possible and may also be overly expensive)

Related posts:


Saturday 29 October 2011

'Twisted Radio Waves': Could they be the way out of Spectrum Crunch?


A recent infograph from PCMag.com, summarises the Spectrum Crunch that we may be facing soon. Though in reality its not as bad as it may seem initially, we still have to find a way out of this. Carrier Aggregation can only help to a certain extent as we still need spectrum to do the aggregation.

The following is from a recent article in discover magazine:

Italian astrophysicist Fabrizio Tamburini says a solution may lie in making better use of the frequencies already in use. In a recent paper, he demonstrated a potential way to squeeze 100 times more bandwidth out of existing frequencies.

The idea is to twist radio waves like corkscrews and create multiple subfrequencies, distinguished by their degree of twistedness. Each subchannel carries discrete data sets. “You can tune the wave with a given frequency as you normally do, but there is also a fingerprint left by the twist,” Tamburini says. He and Swedish colleague Bo Thidé hit upon the approach while studying waves warped by the immense gravity of black holes. This past June, the scientists set up a custom dish in Venice and successfully broadcast video encoded in both twisted and normal radio waves across St. Mark’s Basin. (Note this type of wave-twisting is fundamentally different from the better-known circular polarization of light.)

The next step is to design small, cheap smartphone antennas that can transmit and receive the warped signals. If the industry’s appetite for bandwidth is any indication, it may not be long before twisted-radio technology shows up in your new gadgets.

If you are a Physics buff, you can check the paper out here.

The picture above is from Wikipedia section on Light orbital angular momentum.

Saturday 20 August 2011

Lobbying for more Spectrum

The following Video is prepared by Mobile Future which is a coalition in the US of some major companies and have been lobbying for increase in the availability of the Spectrum.


Saturday 13 August 2011

Tuesday 2 August 2011

Cellphone radiation and Cancer

There is an interesting graph in Scientific American (Via Bill Gross on Google+) showing the radiation spectrum of Cell phones and other devices. Click on the image to view full size.


Thing to note: As the graphic above shows, the radiation emitted in this region is nonionizing: it may heat molecules in the body but does not ionize them (that is, set electrons free). Ionizing radiation, which can tear molecules apart and therefore potentially damage DNA—is the greater worry.

In the comments of the discussion, someone pointed out this hand drawn Electromagnetic Spectrum which is very handy.


Click to enlarge

Finally, it is worthwhile checking out the total radiation that we can encounter in different events and their relative values.


Click to enlarge.

Saturday 18 June 2011

Benefit of 1.4GHz for Mobile Downlink

Significant benefits could flow from use of 1.4 GHz band for a supplemental mobile downlink for enhanced multi-media and broadband services, according to a study by Plum Consulting conducted for Ericsson and Qualcomm.

The study by Plum Consulting shows that using the 1.4 GHz band (i.e. 1452-1492 MHz also called 1.5 GHz by the European Parliament or the L-band by the CEPT) for terrestrial supplemental mobile downlink could generate a net present value for Europe of as much as EUR54 billion over a 10 year period.

The band is currently allocated for use by digital audio broadcasting (DAB) services in most European countries -- part of the band is allocated to terrestrial networks and part is allocated to satellite networks. None of these services have developed in the band. Rather in all countries in Europe the satellite part of the band is unused and this is also the case in the terrestrial component in most countries.

There could be up to eight times as much data being downloaded than is being uploaded in mobile networks. This imbalance is expected to grow, as rich mobile content is increasingly made available and as consumer demand continues to soar. The study found that the use of the 1.4 GHz band as a supplemental downlink band for mobile applications is shown to drastically ease capacity, to enable considerably higher user data rates, to substantially enhance the user experience and to provide significant economic benefits.


The value of releasing the 1.4 GHz band depends on whether other substitute spectrum may become available in the next 5 to 10 years. Starting from today, all countries in Europe have planned or are planning to release the 800 MHz and 2.6 GHz bands in the next two years. There is equipment available for use in both bands and services are already deployed in some countries.

Which other bands might be released over the next 10-15 years? Table 3-2 gives a number of candidate bands, ordered by the likely timing for release, including the 1.4 GHz band for completeness. In each case, we summarise the current status of the band, initiatives that suggest it might be a candidate for future release and our views on the possible timing of deployment based on the difficulty of clearing the band and the harmonisation/standardisation initiatives that would need to be undertaken before equipment would be mass produced for the band.

The white paper is embedded below for reference:

Sunday 22 May 2011

LTE World Summit 2011 - Pics and Notes from Day 1

Here are few pics and discussions from the day 1 of LTE world summit 2011. They are quite brief and I will try and add some info from the tweets as well.

Adrian Scrase from 3GPP said that as there are already over 200 operators committed to LTE, its the fastest growing mobile technology ever.

Bart Weijermars from TMobile Netherlands said future growth will be data centric fuelled by appealing terminals, new usages, broadband and ubiquity.

Future challenges include Network sharing, required to keep the cost under control; everyone allowed to roam freely everywhere; all the content is stored in the cloud and voip is the only option for voice.

New services will be possible with the advent of '4G' but care has to be taken because background apps are already using up a lot of capacity.

There is still work that needs to be done on Spectrum, Smartphone challenges and Network of networks.

Huawei has been one of the main sponsors of the event and the award and Ying Weimin spoke on how LTE is the way to more competitive Mobile Broadband.

According to him, wireless solution is a personalized solution and will go everywhere you go.

Spectrum is the main concern though as a combination of low and high frequency will be needed. Hetnets are coming and they will be the future of the networks.

The way forward is to start the LTE with data only and build on top of that. The network should be simple evolution and will contain of cloud baseband, wideband RRU and AAS.

Pocket Wifi is definitely going to be a killer device and Innovative LTE business and Apps will be needed in the long term like Instant LTE broadcast, Wireless Video surveillance, etc.

LTE is faster than expected and this is the reason there are so many operator commitments. Huawei has 40+ LTE contracts and 10 have already been launched. This is just the beginning.


Seizo Onoe from NTT Docomo spoke about Crossy. In fact during Christmas the employees were wishing each other 'Merry Crossy'. Docomo believes that the users dont care about HSPA or LTE so the Crossy is a service they are selling to the users.

Docomo are getting 75Mbps max DL speeds (using 10MHz band). The phones are capable of 100Mbps though (category 3).

Docomo has recently announced 24 new devices. 2 are Wifi routers. Unlimited data plans on the LTE network cost 5000 yens.

On the spectrum side they are expecting the LTE network to co-exist with UMTS and will be using the 2.1GHz band. In fact Docomo thinks that 2.1GHz should be the universal band that all devices should support so In future when the networks are deployed all these existing devices start working without problems.

The RRE equipment that Docomo has been deploying works with both HSPA and LTE.

Japan has already shutdown its 2G PDC networks but other cannot do the same for GSM. Onoe-san believes that we should stop the evolution of 2G as EDGE has still been evolving and we should focus all the energy into LTE evolution.

Onoe-san did emphasise that LTE is 3.9G and not 4G.

I did check with Onoe-san later that as FOMA was not compliant to the '3G' standards completely, is Crossy compliant to the LTE Specs completely and he said it is.

Onoe-san also said that ETWS was very helpful in the recent tsunami in Japan and services like these should be standardised quickly as they will be useful for someone or the other.


Thomas Wehelier from Informa presented the survey results of LTE ecosystem.

In 2011, the LTE deployments will quadruple but 2012 will have most deployments. Spectrum fragmentation is still prevalent but the core bands for LTE are 800MHz, 1800MHz and 2.6GHz. Capacity still cited as a big driver for the deployments.

TD-LTE represents a new market and new opportunity. In fact Ericsson bills this a year of TD-LTE.


Chris Kimm from Verizon spoke on their 2020 vision.

In Dec. 10 Verizon were covering 110 million people in the US by 2013 the plan is that 290 million will have LTE coverage. In fact LTE was launched in new cities on the day. At the moment though only 250K users are using LTE.

The rate of change is breathtaking and as a result CIO has changed from Chief Information officer to chief innovation officer.

In the Q&A, Chris said that they will deploy voice in 2012 using VoLTE. OTT voice will also be ok.
Tommy Ljunggren from Teliasonera spoke of their LTE deployments.

Last year they had 2 'kids' (as he called their networks) but now they have 4 more. Norway and Sweden got their LTE network in 2009. Network in Finland was launched 30th Nov. 2010. Then on 9th Dec 2010 network in Denmark was launched followed by Estonia on 17th Dec. 2010 and finally Lithuania on 28th April 2011. In fact in Estonia the network was launched 6 minutes after the auction.

Their deployments are in 800/1800/2600 MHz band. This will give them capacity and coverage.

In Sweden the downlink speed is over 20Mbps. In Nordics and Baltics the end users can roam without borders.

Once consumers are using 4G they dont want to go back to 3G. During the royal wedding on Stockholm last year, LTE was used by a TV station to transmit from 6 movable cameras without the need of satellite or any other connection. The transmit was without jitters and a revolution. Nippon TV used LTE to transmit the Noble Peace prize live from Sweden to Tokyo. In fact a bank uses 4G connection as a backup.

TeliaSonera plans to make money by having data caps in place, monthly fees, etc. VoIP would be charged. Right now the charges are €60 for 30GB allowance on LTE.


Cameron Rejali from BT Wholesale spoke on whether the future of mobile was fixed.

According to him WiFi offload is just the start as whenever the speed of the network increases the data usage increases as well.

The network has to do a balancing act. Greater user experience versus network complexity and seamless mobility.

Finally with LTE we will have true convergence at last. The future of mobile is fixed and that of fixed is mobile.

Panel Discussion:

Adrian Scrase brought up the topic of Global Roaming. As there are already 30 bands specified for LTE, do we need a roaming band that should be standardised. Should this band be an Industry initiative or will it be market driven?

The consensus was that this will be market driven.

Question was asked if LTE will be more profitable than previous technology.

NTT Docomo believes that LTE as a technology cannot generate new revenues but the services around it can.

Adrian Scrase asked the question that a lot of Services are defined by the standards but most of them do not get deployed. Does NTT DoComo think ETWS has been defined correctly as per the standards.

Onoe-san from NTT Docomo said that this service has been of utmost importance in the recent tsunami disaster. Even though the service was implemented and available on the phones, it was not used so people were not aware of it. So when the disaster struck everyone was surprised to receive this message. Now everyone knows about this service. Docomo has been using meteorological data since 2009 for this service.

In response to another question Tommy from TeliaSonera said that they will have CSFB next year for voice and VoLTE later. I asked similar question to Onoe-san about the voice support in crossy devices and he said that they will support CSFB. Someone did mention in the panel discussion that VoLTE is not needed and CSFB is enough.

That was my summary of the first day of #LTEWS. You can read the twitter conversations that have much more information.

Sunday 10 April 2011

Cognitive radio – the way out of spectrum crunch?

Another presentation from the Cambridge Wireless Event on Avoiding Cellular Gridlock. One of the ways suggested in the discussions with regards to the 'Geo-location database' (see slide 12) is that they could also be done using Smart Grids. Though it sounds simple in theory, practically we may never see that happen and that would not be due to any technical reasons.

Wednesday 2 March 2011

UMTS-LTE in 3.5GHz

There are two new bands: 3.4-3.6 GHz and 3.6-3.8 GHz decided for Broadband Wireless Access, which are already widely available for licensing in Europe. These bands have earlier been allocated to the Fixed Service on a primary basis in Region 1. Furthermore, the 3.4-3.6 GHz band was allocated to the mobile service on a primary basis and identified for IMT at WRC 07.

These bands constitute a substantial amount of spectrum that will be available in many countries in the short term. In Europe (Region 1) both bands can be used so block sizes could be large for any duplex arrangement.

The UMTS-LTE 3500 MHz Technical Report (3GPP TR 37.801) is already available as a study of current plans in the frequency bands 3.4-3.6 GHz and 3.6-3.8 GHz for UMTS and LTE systems. Specification work is due for first publication in March 2011 (TSG#51), with a series of specifications updated or being created.

The technical report is embedded below: