03 February 2009
22 February 2008
Femtocells for Breakfast?
Well, not quite yet, but will we ever get to the "free with Corn Flakes" stage? Who knows?
Femtocells are low-power wireless access points that operate in licensed spectrum to connect standard mobile devices to a mobile operator’s network using residential DSL or cable broadband connections.
Certainly, since I first came across the concept back in 2006 after some discussions with Ubiquisys, the whole world seems to have gone Femtocell crazy. The Mobile World Congress show in Barcelona last week was described by some as a "Femtocell Frenzy" - event the BBC news reports picked up on the things - meaning that surely the technology has now gone mainstream?
One of the most significant milestones to this technology's mass adoption was the announcement by Netgear of the first commercially available femtocell and combined xDSL modem, router, WiFi access point and four port switch. I want one! Notably Netgear pipped their arch rivals Linksys (a division of Cisco, who have invested in ip.access, another femto manufacturer) to the post.
Some of the initial concerns I personally held about this technology were to do with the ability to maintain the 100ppb frequency stability (required by 3GPP for handset/macro network interoperability) of the air interface in such a consumer device. Imagine your Granny coming home from Carphone Warehouse (for example) with her shiny new 3G handset and Netgear femtocell - she wants to able to plug it in and make calls - has the technology matured enough to be a true plug and play solution? IEEE1588 is being positioned as a possible mechanism to get stability into the box, whilst good old NTP is favoured by some.
Top Ten femtocell plus points:
Femtocells are low-power wireless access points that operate in licensed spectrum to connect standard mobile devices to a mobile operator’s network using residential DSL or cable broadband connections.
Certainly, since I first came across the concept back in 2006 after some discussions with Ubiquisys, the whole world seems to have gone Femtocell crazy. The Mobile World Congress show in Barcelona last week was described by some as a "Femtocell Frenzy" - event the BBC news reports picked up on the things - meaning that surely the technology has now gone mainstream?
One of the most significant milestones to this technology's mass adoption was the announcement by Netgear of the first commercially available femtocell and combined xDSL modem, router, WiFi access point and four port switch. I want one! Notably Netgear pipped their arch rivals Linksys (a division of Cisco, who have invested in ip.access, another femto manufacturer) to the post.
Some of the initial concerns I personally held about this technology were to do with the ability to maintain the 100ppb frequency stability (required by 3GPP for handset/macro network interoperability) of the air interface in such a consumer device. Imagine your Granny coming home from Carphone Warehouse (for example) with her shiny new 3G handset and Netgear femtocell - she wants to able to plug it in and make calls - has the technology matured enough to be a true plug and play solution? IEEE1588 is being positioned as a possible mechanism to get stability into the box, whilst good old NTP is favoured by some.
Top Ten femtocell plus points:
- Better 3G coverage indoors when coverage is there but weak
- Create 3G coverage indoors where coverage hasn't yet been rolled out (e.g. rural areas)
- Uses a standard 3G handset - no need to change your phone!
- "Free" Voice calls via the 3G handset when connected to the femtocell
- "Free" Data calls via the 3G handset when connected to the femtocell
- Single handset for all voice calls (no reliance on the landline for voice!)
- Frees voice/data traffic from macro cellular network - effectively increases capacity for free!
- Single femtocell can handle a handful (5?) of mobile handsets - i.e. get the whole family to take services from one operator.
- Direct delivery of Broadband Access to where the consumer is!
- The handset operates at much lower RF power as it is close to the femtocell.
11 February 2008
Carrier Class NTP
So, what with IEEE 1588 (PTP, Precision Time Protocol or whatever you want to call it!) about to be officially released from the confines of the IEEE ballot process sometime later this year, NTP seems to making a bit of a comeback...
Take the concept of hardware assistance from 1588, change the update rates and filter/servo algorithms from "Standard" NTP (whatever that is!) and what do you get? This thing termed "Carrier Class" NTP - ccNTP - also including a magical sprinkle of traditional Telecom Sync ideas (PRC traceability, redundancy etc.)
In terms of a proper standard - who knows? NTP V3 is the latest RFC release, V4 working party still deliberating over things. TICTOC have somewhat confused the issue (for ccNTP at least) by setting their scope as all things timing over network related...
Time to wait and see?
Take the concept of hardware assistance from 1588, change the update rates and filter/servo algorithms from "Standard" NTP (whatever that is!) and what do you get? This thing termed "Carrier Class" NTP - ccNTP - also including a magical sprinkle of traditional Telecom Sync ideas (PRC traceability, redundancy etc.)
In terms of a proper standard - who knows? NTP V3 is the latest RFC release, V4 working party still deliberating over things. TICTOC have somewhat confused the issue (for ccNTP at least) by setting their scope as all things timing over network related...
Time to wait and see?
19 October 2006
UK National Grid - 50Hz or thereabouts...
National Grid Frequency
Thinking about using the mains frequency as a good source of frequency stability lead me to the National Grid's website, and via the magic of Google to this:
(meter from http://www.dynamicdemand.co.uk/grid.htm)
That has to be one of the coolest things I've seen!
Thinking about using the mains frequency as a good source of frequency stability lead me to the National Grid's website, and via the magic of Google to this:
(meter from http://www.dynamicdemand.co.uk/grid.htm)
That has to be one of the coolest things I've seen!
11 September 2006
Galileo Galileo

Well, before you know it, Galileo will be here. (Well, 2010-ish anyways)
The latest call for R&D ideas has just closed.
There's a seminar starting tomorrow (12/9/2006) relating to Satellite Navigation Regulated Applications in Brussels...
GNSS for Europa?
07 September 2006
Post-Prague posting...

Well, the Prague MasterClass completed successfully, with some positive feedback. Delegates from GTS Novera, Vegacom, Telefonica O2 and Vodafone.
Must be difficult for the attendees, not only have they got to grapple with the intricacies of Network Synchronisation (which, lets face it, is not one of the most exciting subjects to have to sit through two days of!), but to do it in a Second Language is even more taxing - their heads must still be in melt-down! I'm sure I couldn't even begin to comprehend what a "5th overtone AT cut quartz oscillator" might sound like in the Czech language... ?
I also got the chance whilst in Prague to check out the Corinthia Towers hotel, the venue for this year's ITSF (International Telecom Synchronisation Forum). What a stunning venue! Not only 5-star luxury, but a 25th floor conference suite with stunning views over Prague!
Got to sample some local treats too - like Pilsner Urquell! And I thought hilst I was there, I should really try some local food, like "Sausages and Red Cabbage" and "Beef Goulash and Dumplings". Very impressed! Excellent, beer, excellent food, very friendly and helpful people!
04 September 2006
Prague MasterClass Sep 2006
So tomorrow, 5/9/2006, the Symmetricom MasterClass starts in Prague (Hotel Meritum) at 08:30...
Topics Include:
Chronos
Topics Include:
| Introduction to Synchronisation |
| Fundamentals of Synchronisation |
| Synchronisation Elements |
| Standards |
| Quality Metrics & Testing |
| Time Synchronisation (NTP & PTP) |
| Sync over SDH & WDM |
| Core Network Sync |
| Access Network Sync |
| Next Generation Network (NGN) Sync |
| Mobile Networks |
| Architecture & Planning |
| |
Chronos

