Your phone is actually far more battery-efficient when it's able to only use LTE (i.e., if your carrier supports Voice over LTE). It's having to have both radios on (one for voice and one for data) that is hard on the battery.

Not exactly. When it's on LTE and doesn't support voLTE, the signaling is used here to search, connect, and handoff to HSPA or GSM (or CDMA). It increases the call setup time, but it isn't actually a major factor in battery life.

GSM will win most in battery efficiency due to it being a TDMA based standard that pulses the radio off and on. But LTE has improved a long way since the early days.

UMTS and HSPA were fine on battery life and they were CDMA technologies. The big difference is the extra work basebands have to do to handle new modulation technologies as well as the extra CPU time it takes to handle more data. More efficient CMOS processes, baseband designs as well as ARM core designs have been the main cause behind power efficiency in LTE-enabled devices.

Maybe you remember a different history than I do. WCDMA/HSPA was poorly designed early on to tackle smartphones and had terrible battery life and performance.

To summarize pre-2012 HSPA:

- Basically, HSPA phones until around 2011 or so stayed in a higher power state much longer than they should have.

- People got pissy about having crap battery life.

- Manufacturers responded by doing proprietary hacks to send modem into lower power state.

- Cell networks essentially got DDOS'd as phones sent nonstop signaling to negotiate different power states.

- Phones now not only got poor battery life, but also barely operated on the now congested network.. remember the at&t iphone monopoly days before 2012 in major cities, it was a bad time.

3GPP Rel8 came about to fix the issue for good by moving power state control to the towers. Here's an article explaining the technicals of it: http://blog.3g4g.co.uk/2010/10/fast-dormancy-in-release-8.ht... Easier read: http://www.3glteinfo.com/fast-dormancy-in-3gpp/

Would agree though that process size and baseband optimization is helping the LTE situation. Differences are very small and Apple actually quotes better LTE life on the SE than 3G. LTE really came into its own in just the past 2 years.

FYI, AT&T will shut down their 2G network by the end of the year: https://www.att.com/esupport/article.html#!/wireless/KM10848...

Thank God I'm not in the US. I wonder what will happen to all the embedded stuff using low-power 2G chipsets because they transfer data via SMS or CSD/GPRS?

I'm especially thinking about car/truck theft systems. That's going to be expensive to retrofit these...

I work in the automotive industry and the 2G shutdown announcement caused a bit of an uproar for car dealerships that install GPS/starter interrupt devices in the vehicles they sell (for purposes of repossession). Most dealerships buy these devices in bulk, and as I recall from a conference I went to a year or two ago only one of the major providers was offering a partial discount on the price of more modern 3G units for those with soon to be obsolete 2G stockpiles.

Australia is also shutting down 2G next year. They're trying to free up spectrum for more 4G and possibly 5G

T-Mobile has committed to keeping their 2G network operational until 2020 for these M2M devices - and they support the same GSM bands as AT&T does. Unless these device manufacturers want to rush to put LTE radios in everything they'd be wise to just replace everything with T-Mobile SIM's and work on a better upgrade plan over the next 4 years.

I don't know how comprehesive this is, but clearly AT&T is not the only one (or US the only market affected): http://www.zdnet.com/article/optus-announces-2g-network-shut...

Currently seeing this with the Nissan Leaf. It has a 2G modem built in for their Carwings service. Nissan has sent out a letter that the car will need an update for the data features to keep working, but no details on cost or availability. My local dealer has no idea either.

Are you in the UK? We're installing "smart" gas and electricity meters, which use 2G, but industry analysts are predicting the cessation of 2G here by 2020. Awesome!

Maybe it's time for swappable wireless transceivers? Something along the lines of SFP?

Won't help much, because the antenna and coax cable has to meet the correct specs for the frequencies used by the transmitter.

T-Mobile isn't shutting this down anytime soon. Those customers will have to move there (same frequencies anyway).

At least from the operator's perspective it's more efficient if you are in LTE, as you occupy fewer time slots in the spectrum. To the extent that I've seen some operators in Europe offer cheaper data on faster technologies.

I think you're better off bursting the data with the highest speed possible and getting off the spectrum ASAP. Doing IRC on 2G speeds, you'll be transmitting or receiving a decent chunk of the time. With LTE, you'll quickly send or receive your data, then go back to leaving the capacity available for others.

This is part of the big drive to deploy "5G" network technologies in 2020. Better spectrum efficiency means you can support more customers doing data-intensive tasks with fewer cells, that was a big drive behind LTE as well.

With the bandwidth available to LTE connections already I think for the time being we're pretty much topped out on the bandwidth an individual terminal needs, just need to service more of them with less hardware.

If there are no incentives to get new hardware that supports technologies that service more people with less hardware, then deploying them will do nothing.

Because that would be a bad idea.

Why? The phone is idle 90% of the day and thus doesn't need high-bandwidth data in my pocket. In foreground any app could request high-bandwidth data - or, why not, high-bandwidth data while the screen is on and low-bandwidth when the device is in sleep mode.

Because with higher speeds, it returns to idle faster.

2G is also far less power efficient per byte.

The most efficient phone using today's technology would be a category 10 or higher LTE modem /w no 2/3G modems at all. Radio is on for a very short time, then switches back off.

Things have increased in speed so much that if power usage scaled linearly with capacity, using LTE would drain your battery in less than a second. Since they did not scale linearly, you are better off going faster. See "race to idle".