Posts Tagged “WCDMA”
186的卡不能拨号上网了，还能打电话发消息，不知什么时候就彻底不能用了。
移动卡上网，用operamobile流量大增，用operamini既会被封锁，也有可能不支持buzz的留言，惨。
早上收到短信，本月流量6g达到上限，下月自动恢复。
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Posted by Tintin in Travel, tags: 酒, WCDMA, 泸州
喝了三天酒，醉也醉了，吐也吐了，酒真是好，一点不上头。
今天下雨，想继续整理文字和图片，3g信号差，上网慢:(
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中国移动无法登陆google maps 4.0，而联通3g刚才能直接打开google profile中的picasaweb图片。
回到荔湾，这里是3g信号满格却速度奇慢的地方！
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我用186 wcdma 3g的卡，收彩信用cmwap接入点，上网用cmnet接入点，居然全部可以用！
实在想不通。在手机连接状态中很明显只有cmnet和cmwap的连接……
这事情很诡异，也很危险，不知道如何计费……
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3.5G的网络，我就不想了，只有南京和常州的市区有。
回家下了长途汽车，看手机上还连着3G的标志，很幸福。
走到家，大概1里地，直线距离更短，已经只剩下gprs连接了。联通没有edge……
幸好家里还有adsl宽带，用来下nokia maps的地图，非常稳定。
补充一句，距离3.5G不到50km:)
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Posted by Tintin in IT, tags: 3G, 移动, 电信, E52, E71, 联通, iPhone, Mobile Phone, Nokia, Quad-band, Standards, Study, telecommunications, WCDMA
近日困惑全球手机制式频段的问题，查了些资料，整理在此。以wikipedia和nokia官网为准。
- G：generation，代，技术上的更新换代。xG表示x代，简单明了，没有其他含义。具体2G，2.5G，3G……的含义见下文。
UMTS: Universal Mobile Telecommunications System，http://en.wikipedia.org/wiki/UMTS
- 关于频段：
Quad-band，四频，GSM 850/900/1800/1900。经常提起的四频手机，适应全球制式，仅限于2G技术，也就是语音通话。我们需要关注的是3G技术，用于处理数据传输。而一般的3G手机都是支持2G四频段的。
详细资料，http://en.wikipedia.org/wiki/Quad-band
WLAN
A technique to combine the 2.4 GHz and 5 GHz band to give a theoretical bitrate of 600 Mbps.
2G
GSM frequency bands The GSM standard originated in Europe, where mobile phones occupy two frequency bands: one in the 900 MHz range and one in the 1800 MHz range. When GSM technology crossed the Atlantic to the Americas, it was impossible to reuse the same European frequency bands since those had already been allocated to other devices by the FCC. Hence, a different pair of frequency bands were made available for GSM use: the 850 and 1900 MHz bands.
In summary, a quad-band mobile phone is used to designate a phone that can operate in the following GSM frequency bands:
- 850 MHz (U.S./Canada/Latin America/Brazil (Only the carrier Vivo in the south and south-east of Brazil))
- 900 MHz (Africa/Europe/Brazil/Australia/Asia (ex Japan and S. Korea))
- 1800 MHz (Africa/Europe/Brazil/Australia/Asia)
- 1900 MHz (U.S./Canada/Latin America/Brazil (Only the carrier Vivo in the north, north-east and centre-west of Brazil))
Some companies refer to this feature as “World Phone”, due to the variety of bands a quad-band phone supports.
Note that hardly any quad band phones cover GSM-450, a band used in sparsely populated areas or in less developed countries due to its longer range. While a “quint band” phone (450/850/900/1800/1900) is possible, none have yet been announced.
3G
UMTS / HSDPA / HSUPA devices operate in the UMTS frequency bands 800/850/1900/2100 or 850/1700/1900/2100 MHz:
- 2100 (downlink) / 1900 (uplink) for Europe, Africa, Australia, New Zealand, Asia (including South Korea and Japan) and Brazil (usually referred simply as UMTS2100)
- 1900 for North and South America
- 2100 (downlink) / 1700 (uplink) for WIND Mobile and T-Mobile USA, called AWS Band (usually referred simply as UMTS1700)
- 900 for Australia (Optus and Vodafone Australia in rural areas), Vodafone New Zealand and in the future in countries that currently use GSM900
- 850 for North and South America, Australia (NextG), New Zealand (Telecom XT)
- 800 for Japan (NTT DoCoMo in rural areas)
Note that being UMTS / HSDPA / HSUPA quad band doesn’t mean that phone is a GSM / GPRS / EDGE quad band. However nearly all HSUPA quad band devices are EDGE quad band too.
Five and Six band phones (800/850/900/1700/1900/2100) are possible but none have been announced.
- 关于中国3G的频段：中国电信获得1920-1935MHz和2110-2125MHz频段，中国联通1940-1955MHz和2130-2145MHz频段，而中国移动获得的频段是1880-1900MHz和2010-2025MHz，其3G标准是基于TDD模式的。
需要注意：2100MHz只是一个标准，并不是说仅支持2100MHz，联通的频段是完全符合2100Mhz范围的。具体范围懒得查了。
- 关于Nokia：同一款手机以小型号代表销售地区不同，而支持的WCDMA网络频段也不同。在Nokia手机输入*#0000#可以查到具体小型号。
以风靡全球的E71为例
# E71-1 Quad-band EGSM 850/900/1800/1900, WCDMA 900/2100 HSDPA
# E71-2 Quad-band EGSM 850/900/1800/1900, WCDMA 850/1900 HSDPA
# E71-3 Quad-band EGSM 850/900/1800/1900, WCDMA 850/2100 HSDPA
水货的E71如果不幸买到了美国版本E71-2是无法支持国内联通的WCDMA频段的。
以我关注的E52为例，这个机器没有发行美国版本
# WCDMA 900/2100 (Nokia E52-1)
# WCDMA 850/2100 (Nokia E52-2)
无论购买哪里的E52机型，都能支持联通的WCDMA频段，同样都不可能在美国使用。
Nokia E系列更多资料：http://en.wikipedia.org/wiki/Nokia_Eseries
顺便说一下iPhone，同时支持850/1900/2100MHz频段，可以在中国，美国和欧洲通行使用3G。
- UMTS技术和频段的其他资料，这里说的远不如wikipedia清楚。
http://www.umtsworld.com/umts/faq.htm
What are the different types of 3G networks?
ITU Recommendation ITU-R M.1457 specifies five types of 3G radio interfaces:
• IMT-2000 CDMA Direct Spread, also known as UTRA FDD including WCDMA in Japan, ARIB / DoCoMo recommendation. UMTS is developed by 3GPP.
• IMT-2000 CDMA Multi-carrier, also known as Cdma2000 (3X) developed by 3GPP2. IMT-2000 CDMA2000 includes 1X components, like cdma2000 1X EV-DO.
• IMT-2000 CDMA TDD, also known as UTRA TDD and TD-SCDMA. TD-SCDMA is developed in China and supported by TD-SCDMA Forum
• IMT-2000 TDMA Single Carrier, also known as UWC-136 (Edge) supported by UWCC
• IMT-2000 DECT supported by DECT Forum.For more information about 3G air interfaces, download ITU “What is IMT-2000″ presentation (2.5Mb!). Note that page 3 does not classify CDMA2000 1X as 3G, but page 6 does.
please see ITU presentation page.
Some 2.5G systems (GSM GPRS, IS- 95B and CDMA2000 1X (?)) will be able to deliver 3G services, so it will be difficult for users to see the difference. |
What are the UMTS frequencies and channel spacing?
1900-1920 and 2010-2025 MHz Time Division Duplex (TDD, TD/CDMA) Unpaired, channel spacing is 5 MHz and raster is 200 kHz. Tx and Rx are not separated in frequency
1920-1980 and 2110-2170 MHz Frequency Division Duplex (FDD, W-CDMA) Paired uplink and downlink, channel spacing is 5 MHz and raster is 200 kHz. An Operator needs 3 – 4 channels (2×15 or 2×20 MHz) to be able to build a high-speed, high-capacity network.
1980-2010 and 2170-2200 MHz Satellite uplink and downlink
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