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.
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 iFixit.com‘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:
- Create a modular RF section that can be user changed, perhaps embedded with the SIM holder???
- 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…)
- 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.
That’s it folks….
Oh yeah, Fujitsu transceiver launched the other day and would work here too…