Currently viewing the tag: "CDMA"

iPad LTE pic I have written about my ire with Apple regarding their design decisionsThe basic complaint I have with the OEMs (Apple, Samsung, etc…) is that their LTE product design forces the end user to purchase a network specific mobile device. For example, I purchase a Band 13 device (VZW), I cannot then change my mind and go to ATT (Band 17) etc… Of course network operators don’t prefer this capability but let’s ignore that for the moment. Technologically, the ability to do this was limited by (A) the requirements of the devices and (B) the capability of the components in the devices.

Requirements as drivers to network locked devices.

Today’s mobile networks topologically, in the US from a data perspective,  are LTE overlays on existing 2G and 3G network coverage. This is a deployment scenario caused by the reality of the economy, risk aversion of operators etc and whatever. The requirement/expectation is end user  device is usable throughout the entire network coverage area of the network’s operator. Thus, if the LTE coverage ends, the device must gracefully hand down/over to 3G and resume data communications. This means a 3G radio and 4G radio is required to interact with the 2 networks (3G/4G.) 

Currently voice is carried over 3G and not VoLTE yet so this sets up more of the same 3G/4G multi-radio requirements.

Summary: Pure LTE device like a smartphone that uses something like VoLTE  for voice requires one radio and path at a time, today’s voice enabled devices require 2 radio paths. Data only devices can utilize a single radio path but are still hamstrung by the spectrum used for EVDO/HSPA as a fallback to LTE coverage holes ultimately requiring dual radio performance for smooth transitions. Oh yeah, CDMA EVDO handovers are better with eHRPD blah blah but I’m assuming a perfectly state of the art, fully capable device and network.

Capability of components

ipad3 teardown picI have written about the iPad radio design, and the key take aways were the RF chain required Apple to include band specific components to facilitate the multiple radio and/or paths required. There have been some improvements since I’ve moaned and I will go through some of those.


Firstly, let’s look at the antenna. If your load (includes antenna) is RF mismatched in the circuit with the amplifiers, duplexers, filters etc…the efficiency of the radio transmission/reception could suffer a great deal. This means more energy required to transmit/receive, possible harmful interference control measures required and end users end up paying more for poor performance in the end. I mention this because the previous crop of device antennae were not well suited for wide band use, like 700MHz through AWS 2100MHz in the same elements. 

Skycross,Skycross Logo a Fremont, CA company has recently announced some technology that can be helpful here. Here is information from their site:

SkyCross’ three core technologies contribute to addressing the growing number of frequency bands required for LTE and carrier aggregation.

  • iMAT allows a single antenna to act like multiple antennas through the use of multiple feedpoints. Each feedpoint accesses the single antenna as if it were two or more independent antennas, highly isolated from each other. This enables very efficient and compact antenna designs. Developers can combine the iMAT design with other antenna requirements to form a multi-band, multi-protocol antenna module.
  • VersiTune provides an advanced tunable antenna solution for multi-band 4G LTE devices in a single antenna structure. SkyCross can therefore actively tune an antenna from frequency band to frequency band accurately so that the antenna meets the many needs of a single operator or the frequency band requirements of multiple operators simultaneously.
  • MatchTune enables a single antenna structure to uniquely fine tune within a given LTE frequency band, which both enhances performance for a given frequency or for multiple simultaneous frequencies when employing carrier aggregation.

These technologies also enable ODMs and OEMs to improve the performance of their mobile devices, while concurrently reducing costs and shrinking the form factor of their products.

Here’s a good paper about their Isolated Mode Antennas (iMat).

So, yesterday’s devices required either poor efficiency or multiple antennas to support multiple air technologies and bands and now there is Skycross technologies that address these issues. OEMs can design true MIMO devices with good efficiency, in a reasonably small package. I think Apple at some point mentioned this problem with respect to their support for SVLTE in the Verizon version of their devices. Check this off the list of problems.

The next item on the list is the transceiver. I have mentioned Qualcomm’s WTR1605 previously, and this part essentially offers an expansion of bands and radio technologies over previous generations such that a typical 3G/4G band scenario that requires support for Bands 1,4, 12,13, 17 and 25 for LTE and PCS/AWS/800MHz cellular for CDMA. Furthermore, simultaneous support for 11 RX ports and 9 TX ports allow simultaneous multiple radio paths with dedicated PA/LNAs.

AnandTech went into some detail on the WTR1605L for your purchasing or RF hardware engineering pleasure in their blog: The State of Qualcomm’s Modems – WTR1605 and MDM9x25 (Actually, I liked the detail since Qualcomm didn’t publish any.)

WTR1605L RFIC by QualcommQualcomm says:

The WTR1605 will be Qualcomm’s first Radio Transceiver in Wafer Level Package and will be a highly integrated radio transceiver with multi-mode (LTE FDD, LTE TDD, CDMA, WCDMA, TD-SCDMA, GSM) and multi-band support. The WTR1605 will be optimized for low power consumption and small footprint and will integrate a high performance GPS core with GLONASS support. Samples of the MDM9615, MDM8215, WTR1605 and PM8018 are anticipated to be available in late 2011.

Lastly, the 3G/4G MODEM (baseband) is solved with Qualcomm’s 9200/9215 and 9600/9615/9625 parts support GSM/EDGE/WCDMA/CDMA/EVDO/and LTE the technologies of interest here. So we are nearly there with 3 parts. There is something missing though.

The Missing Link

the missing link image

So what’s stopping us from a single multimode multi-band design to serve all networks and end users? The Power Amplifier (PA) and Low Noise Amplifier (LNA) situation. I’m not going to go too deep here because for multiple reasons but on the face of it there are many extra components that would be needed to support all of the Bands 1,4, 12,13, 17 and 25 with MIMO for LTE and PCS/AWS/800MHz cellular for CDMA. It’s not impossible and there are some design decisions that can be made if the OEM is willing to live with extra band specific LNA/PA’s on board. The downside is without any magic, they will take up extra space, create more heat and consume power with or without use. I think there is a better way (Custom silicon) that Apple and Samsung could probably bring to bear more quickly than any other OEMs.  

There You Go

So as you can see, there are 2 paths and on 1, we are tantalizingly close to having universal mobile devices. Oh yeah, as I have mentioned before you will probably need a removable UICC too and Apple has this design presently.  The Path 1 fix with a universal mobile device, when to expect the LNA/PA/duplexor/filter solution? Like I said, an innovator like Apple or Samsung could knock it out rapidly (assuming quickly with core purchased IP from SkyWorks, TriQuint etc…) like mid this year. Else, the groundhog will see it’s shadow and we’ll be having to check at the end of next winter. On the Path 2 fix, implement VoLTE, make LTE ubiquitous and stop using 3G networks, that will take a wee bit longer.



 Now the Blogosphere is incessantly echoing this story … I first noticed in GigaOM, their story is really Fear Uncertainty and Doubt (FUD) extremist journalism (how’s that?) Their story is linked below.

Voice Calls Over 4G LTE Networks Are Battery Killers

The key quote is:

The results of those tests should give carriers and consumers pause. The average power consumption for a 10-minute CDMA circuit-switched call was 680 milliwatts (mW), while the average consumption for a VoLTE call of the same duration was 1,358 mW. That’s double the power drain. Spirent estimated that on a full charge, its test smartphone could support 502.6 minutes of talk time using CDMA only, but the same charge would deliver just 251.8 minutes of talk time using VoIP on the 4G network.

So as a quick refresher, VoLTE (Voice over LTE) calls are similar to the 3G/2G counterparts with VoCODING and so on, but are carried like VoIP, over LTE packets back to the network, where instead of a circuit switch there is an IMS for calls etc etc…

Some related info from before…

Mobile Wireless HD Voice Today and VoLTE in the Future

 Firstly measuring battery consumption is a brute force thing to do here but it does expose the maturity of VoLTE clients at the moment, so I will give them that. The FUD part of it is that the client on the device they tested is really not like anything on a 2G/3G voice phone today. Most of the grunt work of a 2G/3G call takes place in hardware on the phone, with the phone’s UI being the only significant software piece. Voice calling has been optimized in hardware over the years to consume very little power as there is no need for memory, CPU etc… 

On the other hand, the current crop of VoLTE clients are running the whole VoLTE protocol ‘stack’ (SIP + more) in software plus running the VoCODING at this point in software. The bottom line is today’s VoLTE clients are CPU hogs that do use CPU, memory, UI, etc…but are very UN-OPTIMIZED. Let’s give the developers a year or two to optimize the solution and come back and measure. In the end, there will be no difference in power consumption on average.

Let’s stop getting hysterical!

Update: Forgot that Artiza Networks has a nice and clean version. Mine looks like a messy room in comparison. :) See bottom.

Just sharing this, it’s something I did before and forgot where I used it. I think I summarized some details, such as the millions of IMS pieces but broke out important functions such as HSGW vs PDSN and IWS etc for clarity. Enjoy…

The Network Mona Lisa


This version was created by Artiza Networks…

OK, OK, sorry I couldn’t resist. Argela comes out with their FENG, Femto Notification Generator that is and I decided it was too good to pass up an opportunity to be punny. (Yes I pundit…kidding, kidding…)  So FENG is a network function designed to integrate into 3GPP WCDMA and 3GPP2 1X CDMA based core networks, but seemingly not LTE yet but this is probably a matter of time, and sniffs message flow over the Iu-h, Iu-CS, and A’ and MAP interfaces (switch and BSC interfaces) and creates notifications based on network events (messages) such as registrations etc… And note, this is targeted to work with small cells…These notifications are sent to their companion product, the Apps-on Femto Application Server which in turn can notify an application developed with their API to intercommunicate. Typical demonstrations that we gave back in 2004 were actions based on a mobile entering a room such as turning the lights on or off when leaving etc etc… To my knowledge, this is the 2nd commercialized product of this type with Mavenir having a similar capability through their mOne product with the exception Mavenir supports LTE networks. 

Either way, it’s only a matter of time before application providers begin taking us down the connected, Minority Report future of tomorrow. I do think this is a good product announcement.

Full PR is below…

Links: Argela, Mavenir

Bottom line is Argela has their FENG’s out…

Argela’s New Femtocell Product Solves the Problem of Network Detections Critical for  
Value-Added Services and Applications on Small Cell Networks

SUNNYVALE, CA, May 16, 2012– Argela, the next-generation telecommunications solutions provider, today announced its newest femtocell product – the Femto Notification Generator, FENG.  Developed specifically for mobile network operators, the Femto Notification Generator is a key component for offering revenue-generating, value-added services through a femtocell network. Providing immediate data, FENG generates the femtocell-related notifications necessary for many femtocell services and location-based applications.
FENG detects these femtocell-related events by sniffing the operator’s network with the following standard interfaces: Iu-h, Iu-CS, A-Interface, and MAP.  Some of the femtocell events which are detected include entries to and exits from the femtocell network in addition to femtocell registrations and deregistrations.  After immediately detecting important femtocell events, Argela’s FENG then notifies Argela’s APPs-on Femto Application Server which in turn, immediately notifies the applications.  Argela’s two products, the FENG Femto Notification Generator and Argela’s APPs-on Femto Application Server, work together as part of a complete femtocell application solution.
“We wanted to develop a solution that is independent from the femtocell and the femtocell gateway so that any mobile operator could offer value-added services and applications even after they have already deployed their femtocell service,” explained Argela’s VP of Sales, Mr. Oguz Oktay. “It is the notifications issued by our FENG product which enables operators to offer the location-based services and applications through their femtocell network.  And, it is the applications which transform femtocells from a telecom device to a channel for revenue-generating services.”
Argela provides next-generation telecommunication solutions and network infrastructure software to telecom operators and offers a range of small cell products and solutions including femtocells powered by their SmartFemto technology.  The Femto Notification Generator is the newest addition to the Small Cell product line and is a key product in Argela’s Femto Application Suite.   As part of this Suite, Argela also offers femtocell applications including: PromoZone, Track-U and the award-winning, ADz-on Advertising Application.
“At Argela, we are continually innovating and developing new products to help operators and service providers optimize their networks,” said Mr. Bulent Kaytaz, Argela’s CEO. “The Femto Notification Generator is our most recent innovation enabling mobile operators to offer value-added femtocell applications.  It was our aim to provide a complete femtocell application solution for mobile operators so that they may increase the ROI of their femtocell deployment through offering value-added services to their subscribers.”
About Argela
Argela is an award-winning, next-generation, telecom solutions provider.  Collaborating with telecom and mobile operators around the world, Argela provides innovative and integrated turn-key solutions for operators to help them generate new revenue, improve customer satisfaction, contain costs, and decrease churn. Argela’s solutions portfolio includes the award-winning Argela iTV, the award-winning advertising platform, Argela ADz-on, Avatar, IN applications, convergence solutions, and an entire product line of SmartFemto and Small Cell Solutions.   As a member of The Small Cell Forum, Argela is actively addressing the key issues of the femtocell and small cell markets which include defining and developing industry standards which are critical for the deployment of femtocells around the world.  For more information, please visit
Melissa Blythe Johnson
Marketing and Sales Manager
[email protected]

 I try to stay away from UE commentary since there’s so much of my day job that overlaps with this, however it looks like I need to revisit the only device I have commented on for a 4th time. Hopefully this is it. Maybe I should take this as a lesson.

OK here are the previous comments firstly, if you want to catch up to my previous comments. 

No Surprise: New LTE iPad…Shock and Awe: Still 2 Models!! WTF???

Updated, Even More Digging on ‘The New iPad’ Regarding Carrier Lock Down

Follow Up Thinking on ‘The New iPad’ with LTE

In summary, I erroneously assumed Apple would have designed The New iPad with a WTR1605, or equivalent such as the new Fujitsu (see very bottom for specs) RF components. They did not, instead using the RTR8600 (Magellan) and therefore can claim to have spectrum issues to blame on not having a universal iPad that supports all carriers. This was a mistake on my part.

I just want to take this moment to examine why Apple has recently begun issuing refunds to Australian LTE customers on the basis they advertised it to the customers as 4G.

So the logical conclusion is the iPad doesn’t support their spectrum. Telstra has deployed LTE at 1800MHz, which is gaining a lot of worldwide popularity as an LTE band. No, The existing part, RTR8600 DOES have the capability of LTE on this band. So the design issue is not the transceivers it’s the amplifiers (RX and TX.) Here’s‘s picture of the board space for cellular RF and (large)    TechRepublic’s zoom in on the components… (large) 

There’s a TriQuint TQM7M5013 Quad-Band GSM / GPRS / EDGE-Linear Power Amplifier Module…and Skyworks 77460 LIPA  Module for WCDMA / HSPA+ Band IV (1710–1755 MHz)…so the ATT version is in these pictures. This is why Apple has separate versions and why they are having difficulty with Telstra’s 1800MHz LTE with Next G (850 WCDMA) deployment. There’s very limited space plus they’re trying to keep heat dissipation/power consumption down and these constraints together are tough to find parts for.

Regarding Australia, it is possible to cover the bands in the same spaces they have today so I’m only guessing logistics is the issue there. Until then, they will need to back off the 4G claims. 

Here is the confusing amount of possible bands….

I had assumed that there was more space allocated for more silicon so I was wrong about a universal iPad. The way forward for Apple and others is fairly straightforward, to make a universal version, they can:

  1. Create a modular RF section that can be user changed, perhaps embedded with the SIM holder???
  2. Shrink something like battery or use next generation MDM9625/WTR1605  to save some space to allocate for more chips. (Still, doubt you will get all PA/LNA combinations plus you need duplexers etc…)
  3. Go SDR!!! (Software Defined Radio..) Screw this approach, use their existing Cortex type of cores, license some IP from the myriad of A/D and LNA/PA guys out there create a solution that covers all bands.  
#3 is most difficult from a size and power consumption point of view but exactly the type of problem Apple is suited to attack given their resources, desire to create better solutions and end user device pricing. Perhaps one more process shrink of that hardware, like 28um at TMSC or IBM would get them to a ‘close enough for horseshoes and hand grenades so let’s go do it’ ability, I’m not sure. 
Here’s an article on a Wideband Power Amp for SDR that could be a model for the end device.
Lastly, an SDR project would benefit the end users greatly, but I don’t think Samsung or STEricsson would take the initial risk based on their previous performance. On the other hand, for Apple this doesn’t seem risky at all. They are moving something like at least 20M units of mobile devices annually, so developing this module would make sense for the upstream partners that would help make it happen. Apple could organize the effort on a project or tiger team basis with the expectation that the industry will adopt the approach once they have pioneered it. How much of a head start would this give Apple in the marketplace? Guessing about 12months or so at least. Not only that, platforms allows flexibility to really improve RF like through better interference cancellations and so on… Gets me excited to build one just thinking about it.

That’s it folks….

 Oh yeah, Fujitsu transceiver launched the other day and would work here too…

MB86L13A LTE-Optimized Transceiver

 Total coincidence but the other day I was just trying to get in touch with AirWalk when I noticed their management had changed. (it had been a while) So imagine my surprise (not) when I see that Ubee Interactive is purchasing their assets for $45M. AirWalk is a venture funded startup that has got a little traction with Sprint, they have an enterprise femto that supports 1X and EVDO. I remember when Jake Han left us at Samsung to found AirWalk so the arc is complete. The first product line was macro base stations for CDMA, then that quickly changed to micro, then a change to small cells a few years ago. Anyway, Ubee seems to be a better runway for small cells strategy in general as they seem to have lots of funding, some success with their cable modems (complimentary product lines) and a strong Asian connection. Some of the team in Richardson, TX will likely have to move to Denver, Co. That’s an upgrade too!

 I’m still irritated about the LTE iPads being carrier specific. Looking at what public information has been let out here and there, there’s nothing I can discern that really makes me feel a lot better. Let me explain: 

The baseband is most likely the Qualcomm MDM9615. This 28nm processor supports LTE (FDD and TDD), DC-HSPA+, (assuming 1xRTT up to…) EV-DO Rev-B and TD-SCDMA. Essentially most 3G + LTE technologies on one floor plan. Interesting to me is that Qualcomm also points out they have Qualcomm’s Interference Cancellation & Equalization (Q-ICE) algorithm implemented. So no challenges there.

Next, the RF front end (RFFE) or RF interface , the 65nm Qualcomm WTR1605L is a single wafer with a radio transceiver with multi-mode (LTE FDD, LTE TDD, CDMA, WCDMA, TD-SCDMA, GSM, GPS/GLONASS) and multi-band support. Piecing through the various Apple specs, Qualcomm PRs, etc… the bands supported are: GPS, PCS, AWS (Band 4), Lower (Band 12/17) /Upper 700MHz (Band 13) and Cellular (Band 5.) What is unclear is if this revision support for PCS is Band 2 only or includes the G Block as Band 25. Sprint is deploying in Band 25 so this is important. I am going to hazard a guess here, this is a SVLTE capable architecture, it seems to be SVDO capable from the specs. I don’t know if the WTR1605L is dual transceiver or you need to have a 2nd WTR1605L. I suspect it’s dual transceiver, either way Band 13 and Band 17 don’t seem to require anything separate. So there’s enough here to have a voice path too! OK, we don’t explicitly need that so there is enough with the MDM9615 or MDM9625 (It’s shipping NOW!) + WTR1605 to solve the problem of consolidating the design to a single design fits all (but Sprint.) 

The long and short of it is there seems to be no physical reason why Verizon (Band 13) and ATT (Band 17) need to be in different iPad SKUs. Is this problem caused by Qualcomm, perhaps not coming clean on their specs at the behest of the operators? Is this problem caused by Apple in collusion with the operators?

Our world should have a single SKU for iPad supporting all networks, thus allowing us to purchase a single unit which further gives us the flexibility to switch providers over time (I’m ok with contract fees etc…the carriers can trade a subsidy for a penalty.) Heck, why not allow us to tether to this and use it as a hotspot in a pinch. It’s not like I’m going to power up my iPad and leave it in a fixed location for along time to provide WiFi for more than a pinch of time. Furthermore, why not allow me to subscribe to multiple carrier LTE networks so I can switch to the best one in the area, I may be willing to pay them both or all for that privilege. 

It’s not clear who is causing this situation but this is serious BS my fellow consumer!! At the worst case, there should only be 2 SKU’s, a Sprint model and rest of world only until Qualcomm revises its WTR1605L to support Band 25 for Sprint.

Brief Update:

Of course The New iPad is a data only device, thus the RF plumbing is sufficient with the MSM9615 for VZW/ATT support. Assuming Qualcomm updates the WTR1605 to support band 25, then nothing substantially new except a new HW spin will get you to ATT/Sprint/VZW single iPad. If this doesn’t happen in a timely fashion or Apple is willing to invest another $10-$15/unit, they could add other manufacturer parts such as the Fujitsu’s MB86L11A.  This little beast of a transceiver is only 6.6×6.6mm and does most of what the WTR1605 does with the inclusion of Band 25 and others. This is not that hard. The $10 or so of increased cost could be offset with fewer SKUs while the power could be controlled just as effectively so there is not any showstoppers why this isn’t a viable solution to the Band 25 issue. 

For the curious, the Fujitsu MB86L11A data sheet is here.

Now, for the icing on the cake, if Apple was able to score the MSM9625 they would also support Clear (TDD-LTE) and China Mobile (TD-SCDMA/TDD LTE.) Since Qualcomm is shipping this part now there is no need to do anything radical. What this all means is that with a revision to the WTR1605 or different RFFE such as the Fujitsu MB86L11A and plus the MSM6225 instead of the MSM6215, Apple could have a truly single world iPad for the rest of us.

Note regarding iPhone: mostly the same comments apply! It’s 2012, only need 1 device! Since it’s voice device and CDMA needs SVLTE, then I would add a 2nd transceiver. Since takes more cash, more space, more heat and more battery, I would take a serious look at using their Apple modded Cortex processor instead to create a soft transceiver and put some RF HW in front of it first. They have it off the shelf to begin with, secondly they could add RF chains for things like using DUAL polarized diversity antenna in the devices to give us a better user experience (higher rates, fewer drops) to differentiate their premium products. If that’s too tall of an order, then look to other OEM SDR parts second and lastly the tried and true approach of discreet HW as above for the iPad. 

Ok NOW that’s it. I’m done fixing the broken.

Sprint announces 3 vendors for the new multimode basestation plan. (Mission: combine all spectrum into a single box, likely different radio technologies.) They say iDEN is going away (the 800MHz technology) and they don’t say a peep about LTE nor really WiMAX. There’s so much hype around LTE, that caught my attention. What does it all mean?

Source: Sprint

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