WiMAX得標特許費率

中時理財──新聞掃描｜焦點新聞｜中華電、台灣大 不玩WiMAX

特許費率:
北區: 大眾電信(12.89%), 創一首席(6.19%), 威邁思(5.2%)
南區: 威達有線(8.69%), 大同(7.25%), 遠傳(4.18%)
中華電信出價: 2.51%

南北串聯趨勢:
大眾->威達, 創一首席->遠傳, 威邁思->大同

從兩岸科技一百強, 看台灣怎麼辦?

面臨中國　Taiwan，你該怎麼辦？
《數位時代》撰文＝童儀展

從這篇文章中, 可以幫助思考在兩岸競合趨勢的轉變中, 企業未來策略的選擇
有些經典觀察, 深怕遺漏, 特別摘錄如下:

「因為中國以廣大內需為巨額籌碼，並藉由外商與台商的力量，不斷建立起屬於自己對產業的影響力，然後積極發揮基礎研究、軟體優勢，培養出後續一代又一代的本土科技公司，」拓墣產業研究所所長陳清文

新中國概念股所代表的將是，「日後要能被中國業者所善用，並從中獲得中國本地市場，或是隨著中國企業拓展全球腳步而獲取最大利益的台灣企業，」中華經濟研究院所長陳信宏

「勝出或淘汰須跟上中國市場解構腳步然而未來台灣科技業的成長動能，將逐漸來自於市場力量的驅動，而不再是技術力量。這一點，從中國與印度等具備規模經濟的新興市場崛起就可得到驗證，」主筆童儀展

「未來，台灣企業成長模式勢必由過去的技術鏈轉為供應鏈，」拓墣產業研究所大陸研究中心主任張瑞華

WiMAX面談, 初審五家落榜

聯合晚報記者唐孝民台北報導
競價作業預定在7月26日舉行，NCC將於8月3日正式公告得標名單
入闈八家: 大同電信、創一投資、大眾電信、中華電信、遠傳電信、威達有線電視、台信聯合數位 (台哥大)、威邁思電信
落榜五家:中華聯網寬頻、亞太固網、寰宇通、匯僑、旺旺電通

NCC為審慎辦理WBA開放業務，遴聘不同專長領域專家、學者組成審查作業小組，力求第一階段審查作業之客觀及周延。其專業背景及名單如下（依姓名筆劃順序排列）：
一、 電信技術、通訊傳播技術、廣播技術及資訊技術：林一平(交大教授)、林根煌(中山大學教授)、唐震寰(交大教授)、鄧添來(交通部郵電司長)、謝進男(NCC委員)
二、 產業經濟及運輸經濟：王弓(中央大學教授)
三、 傳播：關尚仁(政大教授)、劉幼琍(NCC委員)
四、 財政、會計：趙揚清
五、 財經法律：郭土木

Adrew Keen - The Cult of the Amateur

Internet 上的業餘門外漢正在扼殺文化嗎?中國人有句話, 真理越辯越明, 盡信書不如無書

DIGITIMES科技網-WiMAX執照13家搶6張, 其中有6家投標2區...投標件數南10北9南區執照叫熱門

DIGITIMES科技網-WiMAX執照13家搶6張, 其中有6家投標2區...投標件數南10北9南區執照叫熱門

Sprint行動寬頻設備向‘全IP’發展 .

Sprint行動寬頻設備向‘全IP’發展 .

802.16d Fixed WiMAX -> 802.16e Fixed and Mobile WiMAX -> 802.16m
CDMA 1x -> EVDO Rev A -> UMB (EVDO Rev C)
UMTS WCDMA -> HSDPA -> LTE

技術發展的進度各有不同, 但是大家的共識方向已經達成, 那就是OFDM, MIMO, All-IP
營運商投資過渡型的技術是否能夠即時回收, 或只是再一次被供應商剝削
想挖金礦不成, 倒是造就了賣鏟子的商賈
發展過程中不斷的適時修正, 透過合作結盟, 降低策略風險
這場學費將所費不貲

Sprint, Clearwire Reportedly In Talks About A WiMax Hook-Up -- WiMax -- InformationWeek

Sprint, Clearwire Reportedly In Talks About A WiMax Hook-Up -- WiMax -- InformationWeek

NCC低功率射頻電機技術規範

NCC LP002 低功率射頻電機技術規範

Technology Review: Broadcast Your Life Online, 24-7

Technology Review: Broadcast Your Life Online, 24-7Justin use Sprint's broadband wireless network to send live video signal back to Justin.tv's servers for Lifecasting. Currently, Sprint's Broadband Direct use "fixed wireless" technology for Line-of-sight application. They will launch Mobile WiMAX soon!

Technology Review: Mapping Traffic Flow

Technology Review: Mapping Traffic FlowThe software determines the average speed of roadways across the United States based on two years of historical traffic-speed data collected from commercial fleet vehicles; it uses real-time global positioning software and road sensors from the department of transportation.

Taiwanese High Technology Center Chooses Alvarion's 16E-Based Mobile WiMAX Solution — WIMAX

Taiwanese High Technology Center Chooses Alvarion's 16E-Based Mobile WiMAX Solution — WIMAX

Asia Pacific Telecom Group Chooses Alvarion's Mobile WiMAX 16E-Based Solution for Deployment in Taiwan — WIMAX

Asia Pacific Telecom Group Chooses Alvarion's Mobile WiMAX 16E-Based Solution for Deployment in Taiwan — WIMAX

HP Lab's Location-Based Project :MSCAPE

MSCAPERS
HP Lab launch a project exploring the Location-Based games and city walking tours.

Comparision between AAS and MIMO

The view graph showed above is the summary based on the Nortel's white paper: MIMO or AAS: Key Technology choice in deploying WiMAX.

Unstrung - WiMax/Broadband Wireless - BT Wants WiMax - Wireless News Analysis

Unstrung - WiMax/Broadband Wireless - BT Wants WiMax - Wireless News Analysis
"If the auction gets too aggressive we don't have to play -- we have learned from our past experience. If the price is right, then that's fine. If the price is too high then the MVNO opportunity is the other option," BT Wholesale CTO Matt Beal said

Multicast and Broadcast Services in Mobile WiMAX

Multicast and Broadcast Service (MBS) is defined as an interoperability feature (IO-MBS) by WiMAX Forum and will be tested in Wave 2. MAC and Physical layer related to MBS already defined in IEEE802.16e. Hence, the implementation between MS and BS is more clear. Currently, WiMAX forum not yet define the interface between MBS server and ASN GW but some common industry implementation methodology can be done by vendor.

ASN GW can be a proxy for multicast and broadcast just like an multicast router in IP world. When the MS need to receive multicast service, an IGMP join message for a specific multicast channel will be sent to ASN GW. After some authorization procedure, ASN GW will notify BS to setup multicast channel with the requesting MS through DSA messages which is defined in 802.16. After DSA procedure, MS can receive the multicast channel information from MBS_MAP. Before MS terminate the multicast reception, an IGMP leave message will be sent to AGW. Broadcast service can also be acquired through DSA process and MBS_MAP but bypass the IGMP process.

Mobility function of MBS service can be supported through MBS zone. When the MS moving in the BS culster within the same MBS zone, there is no need to setup new connection ID.

read more ...

Channel Coding and Modulation Required by WiMAX Forum and IEEE 802.16e

Although the Convolution Turbo Code (CTC) is optional in 802.16e, yet both of the Convolution Code(CC) and Convolution Turbo Code(CTC)are required to be implemented in BS and MS according to WiMAX forum's Mobile WiMAX System Profile Release 1 and will be tested in Wave 1. 64-QAM in uplink direction is optional in 802.16e and WiMAX forum's System Profile.

Mandatory Modulation and Coding Rate in Fixed WiMAX OFDM mode

The coding scheme of Reed-Solomon (RS) error correction code can be denoted as (n, k, T), where
n is the number of overall bytes after encoding,
k is the number of data bytes before encoding,
T is the number of data bytes which can be corrected. From the property of RS code, T=(n – k )/2.

The encoding is performed first passing the data in block format through the RS encoder and then passing it through the convolutional code (CC) encoder. Hence,
Coded block size = (the number of overall bytes after RS encoding) / CC code rate

IEEE 802.16-2004 OFDM mode require that the RS-CC overall encoding rate 1/2 should be used as the coding mode when requesting access the network (except in subchannelization modes, which use only convolution code 1/2 and bypass RS code)and in FCH burst.

For example in 16-QAM modulation using RS code (64, 48, 4), the number of overall bytes after RS encoding is 64. And then using CC code rate 2/3, the resulting coded block size is 64*(2/3) ie.96 which is also resulting the overall coding rate 1/2 (ie. 48/96).

Unstrung - WiMax/Broadband Wireless - Sprint Goes Femto With WiMax - Wireless News Analysis

Unstrung - WiMax/Broadband Wireless - Sprint Goes Femto With WiMax - Wireless News Analysis
Femtocell fullfill the coverage at indoors and in-building. Also possible to provide FMC(fixed mobile convergence)service.
picoChip Design Ltd. provide WiMAX reference design using picoArray for total WiMAX MAC and PHY solution including Femtocell of 802.16e OFDMA WiMAX.
The picoChip's WiMAX solution is committed to supporting the standards roadmap and providing customers with a seamless upgrade path to new capabilities, including AAS, MIMO and .16j mobile relay.

Scalable OFDMA selected by WiMax Forum

在802.16-2005 section 8.4.2.3中規定Channel Bandwidth與sampling factor之間的關係, 由Channel Bandwidth(BW), number of used sub-carrier(Nused)與sampling factor可決定sub-carrier spacing, 在相同的sampling factor之下, sub-carrier spacing是固定的
WiMAX forum 為了提高設備實作時的互連性, 特別依據802.16-2004及802.16-2005再明確規範出各項必要及選項功能, 完整描述於WiMAX_Forum_Mobile_System_Profile Release 1.0的文件中,
OFDMA with TDD是System Profile Release 1的基本要求, 台灣選用2.5GHz屬於WiMAX forum定義的2.496GHz~2.69GHz Band Class 3, 移動台MS必須支援整個Band Class的frequency range, 基站台BS則可依BS Vendor宣告支援特定Band Class的部分frequecy range, 但至少需支援到最大channel bandwidth的3倍

Channel Bandwidth為1.25MHz, 5MHz, 10MHz, 20MHz時, 皆為1.25Hz的倍數, 查表得sampling factor n=28/25
Channel Bandwidth為1.75MHz, 7MHz, 8.75MHz時, 皆為1.75MHz的倍數, 查表得sampling factor n=8/7

在802.16-2004 Section 8.4.2.4提到sampling frequency Fs=floor(n*BW/8000)*8000
BW為5MHz的sampling frequency Fs=floor((28/25)*5/8000)*8000=5.6MHz
BW為10MHz的sampling frequency Fs=floor((28/25)*10/8000)*8000=11.2MHz

又sub-carrier frequency spacing可由此推算 deltaF=Fs/Nfft
所以在保持sub-carrier frequency spacing不變的條件下, 只要變動FFT size即可支援不同的channel bandwidth具OFDMA功能, 也就是scalable OFDMA
BW為5MHz若使用Nfft=512, 則BW為10MHz時, Nfft=1024, 而sub-carrier frequency spacing皆維持為deltaF=5.6/512=10.94kHz

Useful symbol time Tb= 1/deltaF, 所以BW為5MHz及10MHz的useful symbol time Tb=1/10.94=91.4usec

在Mobile WiMAX System Profile release 1的section 4.1.1.4中選定cyclic prefix(CP)的必要項目為1/8, 以保護傳送中因multipath fading造成的影響, 所以Guard Time Tg=Tb/8=91.4/8=11.4usec, 加上cyclic prefix 以後的OFDMA symbol duration Ts=Tb+Tg=91.4+11.4=102.9usec, 以Mobile WiMAX System Profile release 1的section 4.1.1.5規定frame length的必要項目為5ms, 因此一個frame可以有5/0.129=48個OFDMA symbol
The guard time can protect the multipath delay spread whose delay time is smaller than guard time. The common pratice about the delay spread in home is 50nsec and the delay spread in outdoors is 300nsec. The guard time in WiMAX is much larger than those common pratice delay spread values.

公式摘要:
Nused= number of used sub-carrier
Nfft= smallest power of 2 greater than Nused
Sampling Frequency Fs=floor(n*BW/8000)*8000
Sub-carrier frequency spacing deltaF=Fs/Nfft
Useful symbol time Tb=1/deltaF
Guard Time Tg=Tb*CP
OFDMA symbol duration Ts=Tb+Tg

使用OFDMA時, 當channel bandwidth變大時只要改變FFT size, 仍可維持相同的Sub-carrier frequency spacing及OFDMA symbol time
In other words, the basic principles of Scalable OFDMA are outlined as:

[1]Sub-carrier spacing is independent of channel bandwidth
[2]The number of sub-carrier scales with channel bandwidth
[3]The smallest unit of bandwidth allocation, based on the concept of subchannels, is fixed and indepedent of bandwidth and other modes of operation.
[4]The number of subchannels scales with bandwidth and the capacity of each individual subchannel remains constant.