在各種有線、無(wú)線家庭網(wǎng)絡(luò)架構(gòu)與標(biāo)準(zhǔn)的競(jìng)爭(zhēng)持續(xù)白熱化同時(shí)，有一種無(wú)線應(yīng)用技術(shù)在今年國(guó)際消費(fèi)性電子展(CES)上竄出頭──Miracast；該技術(shù)可讓使用者將智能手機(jī)、平板電腦等手持式裝置上的內(nèi)容無(wú)線傳送至電視機(jī)的大屏幕播放，在展場(chǎng)吸引不少參觀者駐足。 Miracast展示了一種將個(gè)人多媒體檔案(或者說(shuō)是透過(guò)移動(dòng)裝置隨時(shí)可取得的網(wǎng)絡(luò)內(nèi)容)投影至大屏幕電視的途徑，完全繞過(guò)了廣播業(yè)者或其它服務(wù)業(yè)者所建立的人為限制──這些業(yè)者通常偏好將透過(guò)網(wǎng)際網(wǎng)絡(luò)提供的內(nèi)容圍在高墻里。 市場(chǎng)研究機(jī)構(gòu)IHS資深分析師Brian O'Rourke表示，Miracast其實(shí)就是Wi-Fi Display，是一種讓W(xué)i-Fi芯片擁有點(diǎn)對(duì)點(diǎn)(peer-to-peer)連結(jié)功能的軟件層；雖然Miracast與傳統(tǒng)的Wi-Fi一對(duì)多架構(gòu)不 同，仍是由Wi-Fi Alliance負(fù)責(zé)其標(biāo)準(zhǔn)的建立與維護(hù)。Miracast的特性就是具備能將任何小尺寸屏幕上所播放的內(nèi)容，映像至較大尺寸屏幕上。

YToesmc

除了Miracast，另一種無(wú)線技術(shù)UltraGig 也試圖與之互別苗頭。UltraGig 是芯片廠商晶鐌(Silicon Image)正在推廣的一種專(zhuān)利60GHz技術(shù)，該公司的60GHz無(wú)線技術(shù)是來(lái)自2011年收購(gòu)的SiBeam；后來(lái) Silicon Image賦予了最早是由SiBeam所開(kāi)發(fā)的WirelessHD技術(shù)一個(gè)新名稱(chēng)，就是UltraGig。 本文授權(quán)編譯自EE Times，版權(quán)所有，謝絕轉(zhuǎn)載 本文下一頁(yè)：另一種無(wú)線技術(shù)UltraGig也試圖與之互別苗頭

相關(guān)閱讀：
• 誰(shuí)在劃定智能設(shè)備的連接方式？
• 業(yè)界首款三頻參考設(shè)計(jì)：同時(shí)整合802.11ac和802.11ad技術(shù)
• Marvell率先完成G.hn認(rèn)證，預(yù)測(cè)2013實(shí)現(xiàn)商用大突破YToesmc

{pagination} 讓我們來(lái)復(fù)習(xí)一下：WirelessHD是頻寬最高的無(wú)線視頻傳輸解決方案，目前已可商業(yè)化量產(chǎn)；O'Rourke表示，該技術(shù)針對(duì)未壓縮1,080p視訊傳輸最佳化，因此應(yīng)該不會(huì)有封包遺失或采用MPEG等壓縮格式后所產(chǎn)生的人為問(wèn)題。 Miracast 與UltraGig 在CES都透過(guò)在客廳使用智能手機(jī)的情境，展示了類(lèi)似的點(diǎn)對(duì)點(diǎn)無(wú)線連結(jié)功能。包括聯(lián)發(fā)科(MediaTek)、Nvidia與博通(Broadcom) 等多家芯片廠商都在CES上推銷(xiāo)Miracast技術(shù)，Silicon Image副總裁暨無(wú)線部門(mén)總經(jīng)理Tim Vehling則是在CES的一場(chǎng)論壇上極力凸顯60GHz頻段UltraGig技術(shù)的優(yōu)勢(shì)。 Vehling指 出，UltraGig在實(shí)際展示時(shí)不會(huì)受到任何干擾，但 Miracast 則會(huì)受到眾多Wi-Fi裝置的影響：“人們?cè)贑ES展示Miracast的唯一方式，就是得離開(kāi)展場(chǎng)(例如聯(lián)發(fā)科是在飯店的私人展示間)；有些案例則是耍 一些“造假”手段(如使用MHL纜線)?！? 另一家市場(chǎng)研究機(jī)構(gòu) ABI Research 無(wú)線連結(jié)與半導(dǎo)體市場(chǎng)分析師Peter Cooney同意以上看法，他表示，有部分在CES會(huì)場(chǎng)的Miracast展示，可能是采用 802.11n 技術(shù)：“所以那并不是一場(chǎng)公平的較量?！倍鵁o(wú)論如何：“CES展場(chǎng)是一個(gè)非常嘈雜的環(huán)境?！? Wi-Fi無(wú)疑仍是家庭內(nèi)重要的無(wú)線寬頻技術(shù)；根據(jù)ABI Research的統(tǒng)計(jì)，光是2012年，全球Wi-Fi裝置出貨量就超過(guò)15億臺(tái)。然而這樣的數(shù)字也衍生了對(duì)Wi-Fi裝置在未來(lái)是否會(huì)過(guò)于擁擠、以及在耐用度上的合理憂慮；這正是Silicon Image挾其UltraGig技術(shù)豪賭的負(fù)面情況。 除了沒(méi)有裝置擁塞問(wèn)題，Vehling還強(qiáng)調(diào)UltraGig的低延遲與較高視頻品質(zhì)優(yōu)勢(shì)：“60GHz的Wireless HD延遲不到5ms，”對(duì)游戲應(yīng)用來(lái)說(shuō)特別重要，再加上：“因?yàn)槠湓黾拥念l寬是在60GHz頻段提供，視頻品質(zhì)也較佳；不必使用H.264壓縮?！? 那么，兩種技術(shù)的競(jìng)爭(zhēng)底線何在？當(dāng)然是有關(guān)專(zhuān)利技術(shù)與標(biāo)準(zhǔn)規(guī)格的經(jīng)典爭(zhēng)議。不用說(shuō)，UltraGig的缺點(diǎn)正是：“它是專(zhuān)利芯片解決方案，且Silicon Image 是唯一的供應(yīng)來(lái)源；”IHS 分析師O’Rourke表示：“因?yàn)槿绱怂膬r(jià)格相對(duì)較高，對(duì)消費(fèi)性電子業(yè)者來(lái)說(shuō)是一大風(fēng)險(xiǎn)?！? 據(jù) O’Rourke了解，Silicon Image已經(jīng)開(kāi)始向OEM廠商推銷(xiāo)UltraGig一段時(shí)間，但：“到目前為止沒(méi)有太多成功案例；”他表示，Silicon Image正陷入一種兩難境地──該公司需要沖量以壓低芯片平均銷(xiāo)售價(jià)格(ASP)，但OEM客戶(hù)卻希望在大量應(yīng)用之前就能取得較低價(jià)格：“若有另一個(gè) UltraGig芯片供應(yīng)來(lái)源會(huì)有一些幫助，也能降低對(duì)OEM廠商供應(yīng)風(fēng)險(xiǎn)?！? 不過(guò) UltraGig 與 Miracast 的戰(zhàn)爭(zhēng)也可能出現(xiàn)意料之外的新轉(zhuǎn)折。 本文授權(quán)編譯自EE Times，版權(quán)所有，謝絕轉(zhuǎn)載 本文下一頁(yè)：WiGig與Wi-Fi合并所帶來(lái)的沖擊

相關(guān)閱讀：
• 誰(shuí)在劃定智能設(shè)備的連接方式？
• 業(yè)界首款三頻參考設(shè)計(jì)：同時(shí)整合802.11ac和802.11ad技術(shù)
• Marvell率先完成G.hn認(rèn)證，預(yù)測(cè)2013實(shí)現(xiàn)商用大突破YToesmc

{pagination} WiGig與Wi-Fi合并所帶來(lái)的沖擊 短期看來(lái)， UltraGig 與 Miracast是60GHz專(zhuān)利技術(shù)與2.4GHz / 5GHz Wi-Fi標(biāo)準(zhǔn)的競(jìng)爭(zhēng)，但稍早之前， WiGig Alliance (推動(dòng)60GHz技術(shù)開(kāi)放性標(biāo)準(zhǔn)的組織)與Wi-Fi Alliance宣布合并，有可能出現(xiàn)的發(fā)展是：“WiGig會(huì)并入Wi-Fi，于是802.11ad就會(huì)變成主流60GHz標(biāo)準(zhǔn)?！癆BI的Cooney預(yù)測(cè)。 WiGig 或802.11ad 是采用60GHz頻段中800 或1600MHz的超寬頻(UWB)技術(shù)，傳輸速率號(hào)稱(chēng)最高可達(dá)7Gbps；WiGig Alliance與Wi-Fi Alliance兩個(gè)原本互相競(jìng)爭(zhēng)的組織合并，顯然將會(huì)讓60GHz技術(shù)與2.4GHz/5GHz Wi-Fi標(biāo)準(zhǔn)之間的競(jìng)爭(zhēng)界線出現(xiàn)模糊。 Cooney表示，WiGig 是一個(gè)對(duì)所有WiGig Alliance成員開(kāi)放的標(biāo)準(zhǔn)，而Silicon Image也是該聯(lián)盟成員之一，因此該公司也能取得WiGig技術(shù)內(nèi)容。當(dāng)然，UltraGig已經(jīng)可以量產(chǎn)，Silicon Image的目標(biāo)是推動(dòng)60GHz技術(shù)的起飛成長(zhǎng)，這不會(huì)改變今日UltraGig還是專(zhuān)利技術(shù)的事實(shí)；但在兩到三年之后，也許情況會(huì)完全不同。 未來(lái)UltraGig“可能將擁有Wi-Fi Alliance 與其成員的支持力量，于是另外一種60GHz技術(shù)會(huì)很難(或是不可能)與之競(jìng)爭(zhēng)?！盋ooney認(rèn)為。 他 的預(yù)測(cè)會(huì)不會(huì)太樂(lè)觀？也許會(huì)，也許不會(huì)。根據(jù)ABI Research 預(yù)測(cè)，802.11ad (WiGig)將主要被建置于三頻芯片組(也就是同時(shí)支持802.11n、802.11ac與802.11ad三種標(biāo)準(zhǔn)的方案)，然后未來(lái)移動(dòng)裝置將具備可按照不同使用情況，無(wú)縫選擇任一種通訊協(xié)議的能力。 目前除了Silicon Image 以外，也有其它專(zhuān)攻60GHz技術(shù)的廠商。Cooney指出，其中：“Wilocity 跑得最快，該公司在CES的私人展示間展示了60GHz/ WiGig/11ad 解決方案。”這家Wi-Gig技術(shù)供貨商已經(jīng)與高通(Qualcomm)和Marvell合作推出三頻解決方案。在此同時(shí)，戴爾(Dell)率先發(fā)表內(nèi)建 Wilocity與Qualcomm Atheros合作開(kāi)發(fā)的WiGig/80211a方案之ultrabook。 WiGig 對(duì)Silicon Image的UltraGig未來(lái)發(fā)展將產(chǎn)生如何影響尚不可知；再者，Silicon Image是否會(huì)將其專(zhuān)利技術(shù)化為WiGig解決方案的一部分，還有待觀察。至少現(xiàn)在ABI認(rèn)為，UltraGig不會(huì)一直都是完全隔絕于WiGig或 WiFi的專(zhuān)利60GHz無(wú)線技術(shù)。 本文授權(quán)編譯自EE Times，版權(quán)所有，謝絕轉(zhuǎn)載 編譯：Judith Cheng 參考英文原文：UltraGig: Proprietary blunder or 60GHz future?，by Junko Yoshida

相關(guān)閱讀：
• 誰(shuí)在劃定智能設(shè)備的連接方式？
• 業(yè)界首款三頻參考設(shè)計(jì)：同時(shí)整合802.11ac和802.11ad技術(shù)
• Marvell率先完成G.hn認(rèn)證，預(yù)測(cè)2013實(shí)現(xiàn)商用大突破YToesmc

{pagination} UltraGig: Proprietary blunder or 60GHz future? Junko Yoshida As home networking technology moves to another level, there is a battle brewing between Miracast and Silicon Image's proprietary UltraGig. NEW YORK – While the debate over divergent wired and wireless home networking schemes and standards rages on, one wireless application stood out at the International CES: Miracast. The very idea of being able to wirelessly beam what a user is watching on his or her handheld device (a smartphone or tablet) to a bigger-screen TV struck a chord with a lot of conventioneers. Miracast has shown a path that enables projection of personal media (or Web content readily available on mobile devices) onto a bigger-screen TV. It does so by completely bypassing artificial constraints put up by broadcasters or other service operators who often prefer a walled garden approach to their Internet offerings. Meanwhile, a Miracast vs. UltraGig debate is brewing. As Brian O'Rourke, senior principal analyst at IHS, explains it, “Miracast (previously known as Wi-Fi Display) is a software layer that enables Wi-Fi silicon with peer-to-peer connection capability.” Although Miracast is different from Wi-Fi’s traditional point-to-multipoint architecture, it’s a standard created and maintained by the Wi-Fi Alliance. Miracast’s application has the ability to “mirror whatever is on the smaller screen onto the larger screen." In contrast, UltraGig is a 60GHz technology that Silicon Image is pursuing. Its original 60GHz wireless technology, WirelessHD, comes from SiBEAM, which Silicon Image acquired in 2011. Silicon Image has given WirelessHD technology its own, product brand name: UltraGig. Just to refresh your memory, WirelessHD is the highest bandwidth wireless video transport solution currently available in commercial quantities. O’Rourke explained that it’s optimized for uncompressed 1080p video transmission, so it should not suffer from packet loss or artifacts created by compressed solutions, such as those which use MPEG compression. Both Miracast and UltraGig showed similar demos of peer-to-peer wireless connectivity in a living room using smartphones. Nvidia shows off Miracast. Many chip companies--including MediaTek, Nvidia and Broadcom--touted Miracast at CES. However, Tim Vehling, Silicon Image’s vice president/general manager of wireless division, found CES the perfect forum to pitch and highlight UltraGig’s virtues as it operates on 60GHz. Vehling pointed out that the UltraGig demos “suffered from none of the interference that Miracast has from the many WiFi devices in the market.” He claimed that “the only way people could show Miracast at CES was by doing it off the show floor (a la MediaTek in a private suite at the Sands),” or in some instances, by faking it (using an MHL cable, for example). Peter Cooney, practice director for wireless connectivity and semiconductors at ABI Research, agreed. He said that some of the Miracast demos might have been using 802.11n, “so it would not have been a fair comparison.” At any rate, Cooney said, “it was an incredibly noisy environment at CES.” Wi-Fi: Mega-highway inside the home There is no denying that Wi-Fi continues to be the mega-highway inside the home. More than 1.5 billion Wi-Fi devices were sold in 2012 alone, according to ABI Research. But that, in turn, could give rise to some legitimate concerns over congestion and robustness with WiFi devices in the future. Silicon Image is betting the farm (and its UltraGig) on that side of the argument. Beyond the congestion issues, Vehling offered UltraGig’s low latency and better video quality as advantages. “60GHz Wireless HD offers less than 5ms of latency,” said Vehling, stressing its importance for gaming applications. Further, “due to increased bandwidth offered by 60GHz, video quality is better,” he added. “H.264 compression is not used.” So what’s the bottom line? This, of course, is the classic argument over proprietary technology vs. standardized spec. Undoubtedly, UltraGig’s drawback is that “it is a proprietary silicon solution, and Silicon Image is the sole-source silicon vendor,” said IHS analyst O’Rourke. “This makes it relatively expensive and a risk for CE vendors to offer it.” Silicon Image has been marketing UltraGig to OEMs for a while, “without much success to date,” according to O’Rourke. Silicon Image is “caught in a dilemma – they need increased volumes to drive down chip ASPs, but OEMs want lower ASPs before committing to large-scale integration,” he explained. “Another silicon source for UltraGig would help, as it would reduce the supply risk to PC or CE OEMs of offering UltraGig,” he added. The battle between UltraGig and Miracast could also take a new, unexpected turn, however. Impact of WiGig/Wi-Fi merger Surely, in a short term, this battle is couched as a proprietary 60GHz UltraGig vs. Miracast using a 2.4GHz or 5GHz WiFi technology. But now that the WiGig Alliance (promoting an open standard based on a 60GHz technology) and Wi-Fi Alliance recently announced that they would merge, Cooney predicted, “WiGig will be incorporated into Wi-Fi, and 802.11ad will become the main 60GHz standard.” WiGig or 802.11ad is an ultra-wideband (UWB) technology that uses 800 MHz or 1,600 MHz of spectrum in the 60 GHz band to achieve speeds up to 7 Gbps. The merger of the two competing groups will surely blur the line between 60GHz technology and the 2.4GHz/5GHz WiFi standards. Noting that WiGig is an open standard available to all members of the WiGig Alliance, Cooney explained, “Silicon Image is a member of the WiGig Alliance. So the company does have access to WiGig as well as UltraGig.” Of course, UltraGig is already available, Silicon Image pledges to drive initial 60GHz tech growth. That won’t alter the fact that UltraGig today is still a proprietary technology. But looking into the next two to three years, Cooney sees a very different future. UltraGig “will have the might of the Wi-Fi Alliance and its members behind it. It will be fairly difficult (or impossible) to for another 60GHz technology to compete with this,” he said. Is he too optimistic? Maybe, maybe not. ABI Research’s position is that 802.11ad (WiGig) will be deployed mainly in tri-band chipsets (i.e. 802.11n, 802.11ac, 802.11ad together) and devices will then be able to seamlessly choose which protocol to use depending on the situation. Beyond Silicon Image, other vendors are working in the 60GHz space. Among them, “Wilocity is the furthest down the line and was demoing their 60Ghz/WiGig/11ad solution in their private suite” at CES, Cooney noted. Wi-Gig vendor Wilocity has partnered with both Qualcomm and Marvell to deliver tri-band solutions. Meanwhile, Dell became the first to announce an ultrabook with WiGig/80211ad, developed by Wilocity and Wi-Fi vendor Qualcomm Atheros. How this will affect the future of Silicon Image’s UltraGig is not known. Further, whether Silicon Image will morph its proprietary technology into a part of the WiGig solutions remains to be seen. But at least, for now, ABI Research seems to believe that UltraGig won’t long stay as a proprietary 60GHz wireless technology totally isolated from either WiGig or WiFi.