BLOG DI ICHIRO

ハワイでT-Mobile USAのSIMを持参してもLTE通信にならなかった。
これはDOCOMOのXperia Z2 SO-03FがBand 1、3、21、19に対応しているけど、T-Mobile USAはBand 2、4、12に対応しており。
それが全く合っていないためでした。

だから、私のZ2はハワイでは２Gの速度しか出ませんでした。

ドコモのZ2の周波数は調べると下記となり。
Xperia Z2 SO-03F
通信：
LTE 2100/1800/1500/800　MHz　(Band 1、3、21、19)
WCDMA 2100/850/800　MHz 、
GSM 850/1900　MHz

T-Mobile USAの対応周波数は下記　（　https://support.t-mobile.com/docs/DOC-4988　）
4G LTE
T-Mobile’s advanced 4G LTE network is smoking fast! With incredible speed, you can do more using our nationwide 4G LTE network. 4G LTE delivers up to 50% faster speeds then 3G. If you’re in an area served by 4G LTE, you can expect blazing fast speeds because of our expanded capacity. Check out our coverage map to see all the places we have 4G LTE.*

Frequencies: Band 2 (1900 MHz), Band 4 (1700/2100 MHz), Band 12 (700 MHz)

4G (HSPA+)
With 4G, theoretical maximum download speeds range from 21 Mbps up to 42 Mbps. You can take advantage of incredibly fast download speeds, and even use voice and data services at the same time.

Frequencies: Band 2 (1900 MHz), Band 4 (1700/2100 MHz)

L700
This is also referred to low-band spectrum, it adds increased building penetration as well as covering greater distances. This will be used in metro areas to improve in-building coverage and in rural areas to improve our LTE footprint.

Frequencies: Band 12 (700 MHz)

L1900
L1900 is being used primarily to update our current 2G towers to LTE. Many of our current LTE devices already support L1900 band 2. Check out this device list for phones that are compatible.

Frequencies: Band 2 (1900 MHz)

3G (HSPA)
With 3G, theoretical maximum download of 14 Mbps. With 3G, you can use voice and data services simultaneously.

Frequencies: Band 4 (1700/2100 MHz)

2G (GSM, GPRS, and EDGE)
EDGE, our enhanced 2G service, delivers a theoretical maximum download speed of 236 kbps. GPRS, our 2G service, delivers a theoretical maximum download speed of 114 kbps. Typical speeds are between 35 kbps and 45 kbps. Keep in mind, voice and data services cannot work simultaneously when on GPRS or EDGE.**

Frequencies: Band 2 (1900 MHz)