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Archive for the ‘phones’ Category

ITExpo: BYOD – The New Mobile Enterprise

Sunday, September 9th, 2012

If you are going to ITExpo West 2012 in Austin, make sure you attend my panel on this topic at 1:30 pm on Wednesday, October 3rd.

The panelists are Jeanette Lee of Ruckus Wireless, Ed Wright of ShoreTel and John Cash of RIM.

The pitch for the panel is:

BYOD (Bring Your Own Device) has been in full swing for a couple of years now, and there’s no going back. Enterprises have adopted a policy of allowing users to use their own devices to access corporate networks and resources. With it comes the cost savings of not having to purchase as many mobile devices, and user satisfaction increases when they are able to choose their preferred devices and providers (and avoid having to carry multiple devices). But the benefits don’t come without challenges — the user experience must be preserved, security policies must accommodate these multiple devices and operating systems, and IT has to content with managing applications and access across different platforms. This session looks at what businesses can do to mitigate risks and ensure performance while still giving your users the device freedom they demand.

MIMO for handset Wi-Fi

Monday, February 28th, 2011

I mentioned earlier that the Wi-Fi Alliance requires MIMO for 802.11n certification except for phones, which can be certified with a single stream. This waiver was for several reasons, including power, size and the difficulty of getting two spatially separated antennas into a handset. Atheros and Marvell appear to have overcome those difficulties; both have announced 2×2 Wi-Fi chips for handsets. Presumably TI and Broadcom will not be far behind.

The Atheros chip is called the AR6004. According to Rethink Wireless,

The AR6004 can use both the 2.4GHz and the 5GHz bands and is capable of real world speeds as high as 170Mbps. Yet the firm claims its chip consumes only 15% more power than the current AR6003, which delivers only 85Mbps. It will be available in sample quantities by the end of this quarter and in commercial quantities in the first quarter of next year.

The AR6004 appears to be designed for robust performance. It incorporates all the optional features of 802.11n intended to improve rate at range. Atheros brands this suite of features “Signal Sustain Technology.” The AR6004 is also designed to reduce the total solution footprint, by including on-chip power amplifiers and low-noise amplifiers. Historically on-chip CMOS power amplifiers have performed worse than external PAs using GaAs, but Atheros claims to have overcome this deficiency, prosaically branding its solution “Efficient Power Amplifier.”

The 88W8797 from Marvell uses external PAs and LNAs, but saves space a different way, by integrating Bluetooth and FM onto the chip. The data sheet on this chip doesn’t mention as many of the 802.11n robustness features as the Atheros one does, so it is unclear whether the chip supports LDPC, for example.

Both chips claim a maximum 300 Mbps data rate. Atheros translates this to an effective throughput of 170 Mbps.

Of course, these chips will be useful in devices other than handsets. They are perfect for tablets, where there is plenty of room for two antennas at the right separation.

Sharing Wi-Fi Update

Saturday, January 15th, 2011

Back in February 2009 I wrote about how Atheros’ new chip made it possible for a phone to act as a Wi-Fi hotspot. A couple of months later, David Pogue wrote in the New York Times about a standalone device to do the same thing, the Novatel MiFi 2200. The MiFi is a Wi-Fi access point with a direct connection to the Internet over a cellular data channel. So you can have “a personal Wi-Fi bubble, a private hot spot, that follows you everywhere you go.”

The type of technology that Atheros announced at the beginning of 2009 was put on a standards track at the end of 2009; the “Wi-Fi Direct” standard was launched in October 2010. So far about 25 products have been certified. Two phones have already been announced with Wi-Fi Direct built-in: the Samsung Galaxy S and the LG Optimus Black.

Everybody has a cell phone, so if a cell phone can act as a MiFi, why do you need a MiFi? It’s another by-product of the dysfunctional billing model of the mobile network operators. If they simply bit the bullet and charged à la carte by the gigabyte, they would be happy to encourage you to use as many devices as possible through your phone.

WiFi Direct may force a change in the way that network operators bill. It is such a compelling benefit to consumers, and so trivial to implement for the phone makers, that the mobile network operators may not be able to hold it back.

So if this capability proliferates into all cell phones, we will be able to use Wi-Fi-only tablets and laptops wherever we are. This seems to be bad news for Novatel’s MiFi and for cellular modems in laptops. Which leads to another twist: Qualcomm’s Gobi is by far the leading cellular modem for laptops, and Qualcomm just announced that it is acquiring Atheros.

iPhone 4 gets competition

Thursday, July 29th, 2010

When the iPhone came out it redefined what a smartphone is. The others scrambled to catch up, and now with Android they pretty much have. The iPhone 4 is not in a different league from its competitors the way the original iPhone was. So I have been trying to decide between the iPhone 4 and the EVO for a while. I didn’t look at the Droid X or the Samsung Galaxy S, either of which may be better in some ways than the EVO.

Each hardware and software has stronger and weaker points. The Apple wins on the subtle user interface ingredients that add up to delight. It is a more polished user experience. Lots of little things. For example I was looking at the clock applications. The Apple stopwatch has a lap feature and the Android doesn’t. I use the timer a lot; the Android timer copied the Apple look and feel almost exactly, but a little worse. It added a seconds display, which is good, but the spin-wheel to set the timer doesn’t wrap. To get from 59 seconds to 0 seconds you have to spin the display all the way back through. The whole idea of a clock is that it wraps, so this indicates that the Android clock programmer didn’t really understand time. Plus when the timer is actually running, the Android cutely just animates the time-set display, while the Apple timer clears the screen and shows a count-down. This is debatable, but I think the Apple way is better. The countdown display is less cluttered, more readable, and more clearly in a “timer running” state. The Android clock has a wonderful “desk clock” mode, which the iPhone lacks, I was delighted with the idea, especially the night mode which dims the screen and lets you use it as a bedside clock. Unfortunately when I came to actually use it the hardware let the software down. Even in night mode the screen is uncomfortably bright, so I had to turn the phone face down on the bedside table.

The EVO wins on screen size. Its 4.3 inch screen is way better than the iPhone’s 3.5 inch screen. The “retina” definition on the iPhone may look like a better specification but the difference in image quality is indistinguishable to my eye, and the greater size of the EVO screen is a compelling advantage.

The iPhone has far more apps, but there are some good ones on the Android that are missing on the iPhone, for example the amazing Wi-Fi Analyzer. On the other hand, this is also an example of the immaturity of the Android platform, since there is a bug in Android’s Wi-Fi support that makes the Wi-Fi Analyzer report out-of-date results. Other nice Android features are the voice search feature and the universal “back” button. Of course you can get the same voice search with the iPhone Google app, but the iPhone lacks a universal “back” button.

The GPS on the EVO blows away the GPS on the iPhone for accuracy and responsiveness. I experimented with the Google Maps app on each phone, walking up and down my street. Apple changed the GPS chip in this rev of the iPhone, going from an Infineon/GlobalLocate to a Broadcom/GlobalLocate. The EVO’s GPS is built-in to the Qualcomm transceiver chip. The superior performance may be a side effect of assistance from the CDMA radio network.

Incidentally, the GPS test revealed that the screens are equally horrible under bright sunshine.

The iPhone is smaller and thinner, though the smallness is partly a function of the smaller screen size.

The EVO has better WAN speed, thanks to the Clearwire WiMax network, but my data-heavy usage is mainly over Wi-Fi in my home, so that’s not a huge concern for me.

Battery life is an issue. I haven’t done proper tests, but I have noticed that the EVO seems to need charging more often than the iPhone.

Shutter lag is a major concern for me. On almost all digital cameras and phones I end up taking many photos of my shoes as I put the camera back in my pocket after pressing the shutter button and assuming the photo got taken at that time rather than half a second later. I just can’t get into the habit of standing still and waiting for a while after pressing the shutter button. The iPhone and the EVO are about even on this score, both sometimes taking an inordinately long time to respond to the shutter – presumably auto-focusing. The pictures taken with the iPhone and the EVO look very different; the iPhone camera has a wider angle, but the picture quality of each is adequate for snapshots. On balance the iPhone photos appeal to my eye more than the EVO ones.

For me the antenna issue is significant. After dropping several calls I stuck some black electrical tape over the corner of the phone which seems to have somewhat fixed it. Coverage inside my home in the middle of Dallas is horrible for both AT&T and Sprint.

The iPhone’s FM radio chip isn’t enabled, so I was pleased when I saw FM radio as a built-in app on the EVO, but disappointed when I fired it up and discovered that it needed a headset to be plugged in to act as an antenna. Modern FM chips should work with internal antennas. In any case, the killer app for FM radio is on the transmit side, so you can play music from your phone through your car stereo. Neither phone supports that yet.

So on the plus side, the EVO’s compelling advantage is the screen size. On the negative side, it is bulkier, the battery life is less, the software experience isn’t quite so polished.

The bottom line is that the iPhone is no longer in a class of its own. The Android iClones are respectable alternatives.

It was a tough decision, but I ended up sticking with the iPhone.

First 802.11n handset spotted in the wild – what took so long?

Thursday, December 24th, 2009

The fall 2009 crop of ultimate smartphones looks more penultimate to me, with its lack of 11n. But a handset with 802.11n has come in under the wire for 2009. Not officially, but actually. Slashgear reports a hack that kicks the Wi-Fi chip in the HTC HD2 phone into 11n mode. And the first ultimate smartphone of 2010, the HTC Google Nexus One is also rumored to support 802.11n.

These are the drops before the deluge. Questions to chip suppliers have elicited mild surprise that there are still no Wi-Fi Alliance certifications for handsets with 802.11n. All the flagship chips from all the handset Wi-Fi chipmakers are 802.11n. Broadcom is already shipping volumes of its BCM4329 11n combo chip to Apple for the iTouch (and I would guess the new Apple tablet), though the 3GS still sports the older BCM4325.

Some fear that 802.11n is a relative power hog, and will flatten your battery. For example, a GSMArena report on the HD2 hack says:

There are several good reasons why Wi-Fi 802.11n hasn’t made its way into mobile phones hardware just yet. Increased power consumption is just not worth it if the speed will be limited by other factors such as under-powered CPU or slow-memory…

But is it true that 802.11n increases power consumption at a system level? In some cases it may be: the Slashgear report linked above says: “some users have reported significant increases in battery consumption when the higher-speed wireless is switched on.”

This reality appears to contradict the opinion of one of the most knowledgeable engineers in the Wi-Fi industry, Bill McFarland, CTO at Atheros, who says:

The important metric here is the energy-per-bit transferred, which is the average power consumption divided by the average data rate. This energy can be measured in nanojoules (nJ) per bit transferred, and is the metric to determine how long a battery will last while doing tasks such as VoIP, video transmissions, or file transfers.

For example, Table 1 shows that for 802.11g the data rate is 22 Mbps and the corresponding receive power-consumption average is around 140 mW. While actively receiving, the energy consumed in receiving each bit is about 6.4 nJ. On the transmit side, the energy is about 20.4 nJ per bit.

Looking at these same cases for 802.11n, the data rate has gone up by almost a factor of 10, while power consumption has gone up by only a factor of 5, or in the transmit case, not even a factor of 3.

Thus, the energy efficiency in terms of nJ per bit is greater for 802.11n.

Here is his table that illustrates that point:
Effect of Data Rate on Power Consumption

Source: Wireless Net DesignLine 06/03/2008

The discrepancy between this theoretical superiority of 802.11n’s power efficiency, and the complaints from the field may be explained several ways. For example, the power efficiency may actually be better and the reports wrong. Or there may be some error in the particular implementation of 802.11n in the HD2 – a problem that led HTC to disable it for the initial shipments.

Either way, 2010 will be the year for 802.11n in handsets. I expect all dual-mode handset announcements in the latter part of the year to have 802.11n.

As to why it took so long, I don’t think it did, really. The chips only started shipping this year, and there is a manufacturing lag between chip and phone. I suppose a phone could have started shipping around the same time as the latest iTouch, which was September. But 3 months is not an egregious lag.

3G network performance test results: Blackberries awful!

Thursday, October 1st, 2009

ARCchart has just published a report summarizing the data from a “test your Internet speed” applet that they publish for iPhone, Blackberry and Android. The dataset is millions of readings, from every country and carrier in the world. The highlights from my point of view:

  1. 3G (UMTS) download speeds average about a megabit per second; 2.5G (EDGE) speeds average about 160 kbps and 2G (GPRS) speeds average about 50 kbps.
  2. For VoIP, latency is a critical measure. The average on 3G networks was 336 ms, with a variation between carriers and countries ranging from 200 ms to over a second. The ITU reckons latency becomes a serious problem above 170 ms. I discussed the latency issue on 3G networks in an earlier post.
  3. According to these tests, Blackberries are on average only half as fast for both download and upload on the same networks as iPhones and Android phones. The Blackberry situation is complicated because they claim to compress data-streams, and because all data normally goes through Blackberry servers. The ARCchart report looks into the reasons for Blackberry’s poor showing:

The BlackBerry download average across all carriers is 515 kbps versus 1,025 kbps for the iPhone and Android – a difference of half. Difference in the upload average is even greater – 62 kbps for BlackBerry compared with 155 kbps for the other devices.
Source: ARCchart, September 2009.

Dual-mode technology maturing

Thursday, August 27th, 2009

The Rethink Wireless newsletter is always worth reading. An article in today’s edition says that according to ABI dual mode handset shipments are on track to double from 2008 to 2010, and more than double from 2009-2011 (144 million units to 300 million units).

Rethink’s Matt Lewis cites improved performance and usability as driving forces, plus a change in the attitudes of carriers towards hot-spots. Wireless network operators now often have captive Wi-Fi networks and can use them to offload their cellular networks.

The upshot is a prediction of 300 million dual mode handsets to ship in 2011: 100% of the smartphone market plus high end feature phones.

The attach rate of Wi-Fi will continue to grow. By 2011 the effects of Bluetooth 3.0 will be kicking in, pushing Wi-Fi attachment towards 100% in camera phones and music phones in ensuing years.

Linley Report on Mobile Connectivity Chips Released

Saturday, February 28th, 2009

I have been working for some time on a report about mobile connectivity chips. This is an interesting market, one that is so hot that it is actually going to continue to grow in 2009 as the overall cell phone market declines by 10%.

The term “connectivity” denotes all the radios in a cell phone that are not cellular radios. There are a lot of them. The main ones are Bluetooth, FM radio, GPS and Wi-Fi. Others beginning to appear in handsets are TV and NFC. Further out in time are 60 GHz and White Spaces radios.

The cell phone market deals in massive volumes – about 1.2 billion handsets were sold in 2008. It also has some stringent requirements. The market demands chips that are small, cheap, battery-life conserving and easy to design-in. These considerations have driven chip vendors to combine multiple connectivity radios onto single chips. The first combo chips were Bluetooth plus FM. Then came Bluetooth plus FM plus Wi-Fi then most recently Bluetooth plus FM plus GPS.

Because the market is so big, the competition is intense. The 2008 leaders in Bluetooth were Broadcom and CSR; in Wi-Fi TI, ST-Ericsson and Marvell; in GPS TI and Infineon; and in FM ST-Ericsson and Silicon Labs.

These vendors are leap-frogging each other on performance and features. 2009 will see major changes in market share as some vendors fail to refresh their old product lines, others refresh their product lines but with inadequate products, and new entrants come in with better solutions.

Fixed Mobile Substitution and Voice over Wi-Fi

Tuesday, January 6th, 2009

Getting rid of your land-line phone and relying on your cell phone instead is called Fixed Mobile Substitution (FMS).

A report from the National Center for Health Statistics of the Centers for Disease Control (CDC) shows a linear increase in the number of households that have a cell phone but no land-line, starting at 4.4% in 2004 and reaching 16.1% in the first half of 2008.
US Fixed Mobile Substitution 2005-2008 - source: CDC

These numbers match those in a recent Nielsen report on FMS.

FMS will most likely accelerate in 2009 because of the recession. It will be interesting to see by how much. We will reach a tipping point soon. 13% of households have a landline that they don’t use.

There are about 112 million occupied housing units in the US, and about 71 million broadband subscribers.

So what does this mean for Wi-Fi VoIP? One of the primary reasons for FMS is to save money; it is more prevalent in lower income households. There are two kinds of phone that do VoWi-Fi, smartphones and UMA phones. Smartphones are expensive, and probably less common among the cord-cutting demographic – except that that demographic is also younger and better educated as well as having a modest income – many are students.

Wi-Fi VoIP in smart phones is still negligible, but the seeds are planted: vigorous growth of smart phones, Wi-Fi attach rate to smart phones trending to 100%, a slow but steady opening up of smart phones to third party applications, broadband in most homes, Wi-Fi growing in all markets.

Wi-Fi and the Mobile Internet

Thursday, December 18th, 2008

Admob periodically publishes numbers on the mobile Internet and its usage. The numbers are badly skewed because of Admob’s customer mix. For example Indonesia lists as the second largest mobile Internet market in the world. But if you make your own mental adjustments for this, the numbers are informative.

Admob’s latest report highlights Wi-Fi use in the USA.

Of the ad requests fielded by Admob, in August 2008 9% came from Wi-Fi capable devices: dual-mode phones, iPod Touches and Sony PSPs. In November this number doubled to 19%. Since the numbers for August aren’t broken down, it is uncertain which devices drove this growth, but my guess is that it is due to the booming sales of the iPhone.

Of the requests from Wi-Fi capable devices, the proportion that came over Wi-Fi varied radically. For the iPod Touch and the Sony PSP, 100% of the requests were over Wi-Fi. No surprise there. But on the phone side, a very interesting discrepancy between the iPhone (42% of requests by Wi-Fi) and the HTC phones (16% of requests by Wi-Fi). Since each of the phones uses the same browser for cellular data and Wi-Fi connections, it can’t be an ease of use of the Internet issue. Two other possibilities come to mind: the Wi-Fi may be easier to set up on the iPhone than it is on the HTC phones, or the cellular data speed may be worse on the AT&T network, driving the users to Wi-Fi, while users on T-Mobile (where all the HTC phones listed in the report are) get acceptable performance from their cellular data connection.

The Blackberry data casts a similar light on the question. The two Blackberries in the report were the 8820 and the 8320. The 8820 had the same profile as the iPhone – 40% of the requests came by Wi-Fi. The 8320 had even less Wi-Fi use than the HTC phones – only 8% of the requests came by Wi-Fi. These two phones are both on the same carriers (AT&T and T-Mobile), they have the same Wi-Fi chip (from TI), and their specs are similar.

The clue is in their release dates. The 8320 has been out on T-Mobile for a year, but was not yet released on AT&T in November when AdMob collected their numbers. The 8820 was released by AT&T a year ago, but by T-Mobile only 6 months ago. There are obviously a lot of other variables at work – like 3G versus 2G, for example, and pricing structure, but this looks like evidence that the T-Mobile data network has a more acceptable performance than AT&T’s.