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标题: OFC上的100G 测试展示 [打印本页]

作者: stupid 时间: 2012-3-24 14:35
标题: OFC上的100G 测试展示
本帖最后由 stupid 于 2012-3-24 15:15 编辑

With all the new technology developments on display at OFC/NFOEC 2012 in Los Angeles, it’s no surprise that test equipment companies also touted the results of their efforts to keep pace. And equally unsurprising given the ubiquity of new products related to 100-Gbps, much of the action in the booths of the test instrument vendors revolved around this topic as well.

For example, Agilent Technologies showed off its newly announced N4392A optical modulation analyzer. This instrument represents a significant advance because it combines the optical modulation analyzer with a companion real-time oscilloscope in a single, portable platform. The product offers a direct path toward getting optical modulation analysis on more lab benches – as well as production floors and, who knows, maybe even the field.

前一代4391A
The N4391A optical modulation analyzer offers tools to analyze and quantify the signal integrity of a vector modulated signal (e.g., error vector magnitude and quadrature error). The N4391A is the first optical modulation analyzer offering measurement and compensation of the link’s CD and first order PMD by analyzing the received signals, offering engineers insight into the root cause of constellation distortions. The CD and PMD compensation helps system researchers and engineers quantify their signal quality along the link and down to the receiver input by correcting for CD and PMD distortions in the constellation diagram and displaying CD and first order PMD values in the status line of the N4391A.

这次发布的4392A
handle 32-Gbaud modulation formats and offers 63-Gsamples/s real-time sampling rates, and both optical and differential RF inputs; in fact, it has four differential RF inputs.

While Southern Photonics’ IQScope optical modulation analyzer still needs a separate oscilloscope, it pairs with the equivalent-time variety – which also may make such measurement capabilities more accessible to a wider range of engineers and applications. The concept is potentially attractive enough that Tektronix – which bought Optametra and now offers that company’s optical modulation analyzer in combination with its own real-time scopes – demonstrated a version of the Optametra product that would work with Tektronix’s equivalent-time scopes. This was something of a test case rather than the definite signal of a new product direction, a Tektronix staffer told me.

Meanwhile Southern Photonics scored when it announced a partnership with LeCroy. LeCroy had been left on the outside of the optical modulation analysis space looking in at Agilent, EXFO, and Tektronix when Optametra was taken off the market. Since LeCroy specializes in high-bandwidth real-time oscilloscopes – it showed off the latest version of its LabMaster 10 Zi Modular Oscilloscope System, which can deliver 60 GHz of bandwidth through its Digital Bandwidth Interleave technology – it would not be surprising if a new version of the IQScope optimized to work with real-time scopes was unveiled in the future.

To complement the IQScope, Southern Photonics also announced a 34-GS/s arbitrary waveform generator. The AWG-34G uses Micram’s VEGA DACII ultrafast signal converter to deliver what Southern Photonics asserts is the fastest AWG performance available.

电版本支持225G的DP-QPSK解调和450G的16QAM，光版本的速率翻倍。

The IQScope supports a variety of measurements applicable to R&D analysis and production testing, including error vector magnitude (EVM), IQ phase error, RF gain imbalance and skew, and optical signal-to-noise ratio.

针对16QAM和OFDM等复杂的光调制应用。

Maximum sampling rate 34 GS/s
Bandwidth 18 GHz (Typical)
Memory size 2 Megasamples
Resolution 6 bit
Number of channels per unit 1
Predefined operations Addition, subtraction, multiplication, division, filter and modulation
Built-in patterns PRBS binary and multi-level, sine, triangle/saw-tooth, square, DC and noise

Micram的另一家伙伴HHI也推出了相同的东西，而且支持16个通道的同步

Meanwhile, Tektronix offered new modules for its DSA8300 Digital Signal Analyzer sampling oscilloscope that support optical compliance testing of Ethernet at speeds up to 100 Gbps. That would be the 4x25G version of 100 Gbps, which also got its share of attention at the show.

For example, Discovery Semiconductors displayed its recently announced 25-Gbaud Lab Buddy optical receiver with integrated CDR functionality. The platform uses the GN2426 CDR device from Gennum Corp. (a company that Semtech recently purchased) to enable the O/E and CDR functions to be combined in the same box; thus, the receiver’s linear output and the CDR data can be delivered directly to an oscilloscope or bit-error-rate analyzer from the same source.

作者: 挑战极限 时间: 2012-3-28 17:25
要多少RMB?我想买一套

作者: stupid 时间: 2012-3-29 13:32
标题: RE: OFC上的100G 应用展示
As is the case every year, OFC/NFOEC 2012 in Los Angeles last week featured a variety of technology and application themes. “Cost-effective 100G in the metro” was among the most prominent. Since a combination of a hectic schedule and the (allegedly temporary) inability of our new content management system to support blogging prevented me from posting my standard Reporter’s Notebook trade show items, I thought I’d compensate by filing a few post-show notebook-style stories, of which this is the first.

While 100-Gbps technology has only recently begun deployment in long-haul networks, Ihab Tarazi, vice president, global network planning at Verizon, heralded the advent of metro deployments when he told the audience at the OSA Executive Forum March 5 that he expected to roll out 100G in the metro early next year. Tarazi didn’t say exactly where this might occur, but sources at the show agree that the general opportunity is in links from about 40 km to maybe 600 km (although some suggested even longer runs). Data center interconnect will provide the greatest catalyst for such deployments, most believe, with wireless backhaul offered in explanation as well.

The difference in reach isn’t the only area in which 100G metro will differ from 100G long haul. Whereas the industry rallied around the OIF long-haul DWDM specifications – including the use of dual-polarization quadrature phase-shift keying (DP-QPSK) with coherent detection as the modulation format of choice – the metro appears more of a free-for-all. Four primary options have emerged: DP-QPSK, 16-QAM, 4x25-Gbps (or, really, 4x28G if you include overhead) using optical duobinary (ODB) modulation, and 4x25-Gbps using on/off keying (OOK). And, just to add further spice, module vendors targeting 10x10-Gbps approaches have their eyes on the shorter-reach end of the metro spectrum as well.

[UPDATED] Camps have already started to form around the different approaches. Sources at Transmode and Fujitsu Network Communications told me that they’re fine with DP-QPSK. However, Alcatel-Lucent (Euronext Paris and NYSE: ALU) and Ciena (NASDAQ: CIEN) both touted the applicability of coherent 16-QAM to the metro as well as to 400-Gbps applications. Meanwhile, ECI Telecom announced that 4x25-Gbps development is underway in collaboration with chip vendor Multiphy, while ADVA Optical Networking used the show to demonstrate its previously announced 4x25-Gbps approach. ADVA's 4x25G efforts use ODB; contrary to what we previously reported, ECI Telecom will take an OOK approach.

Participants have described the OIF long-haul effort as a way to “avoid the mistakes of 40G” – that is, so many technology options that none could gain enough market traction to enjoy significant cost reduction. So is the industry in danger of repeating those mistakes in the metro?

Interestingly, few people with whom I spoke believe this to be the case. For example, Karen Liu, an analyst at Ovum, said at a Sunday evening seminar on 40 and 100 Gbps that she believes the 4x25G approach looks enough like what the IEEE has in mind for shorter reaches that it will be seen as an extension of that effort. And Christoph Glingener, CTO at ADVA Optical Networking (FSE: ADV), says that unlike 40 Gbps, 4x25-Gbps approaches don’t require high volumes to deliver cost savings. He asserted that ADVA’s approach is already delivering 100-Gbps capabilities to customers in the field at price points below 10x10 Gbps.

As for 16-QAM, Ciena’s Joe Berthold told the Executive Forum audience that 16-QAM line cards can use optical components designed to the OIF’s DP-QPSK specifications; other sources on the show floor corroborated that assessment. This means that metro 100-Gbps line cards could benefit from the cost-reduction possibilities presented by the entire 100-Gbps coherent marketplace.

Regardless, it appears that carriers will have several options to weigh when it comes time to bring 100 Gbps to their metro networks. Tarazi said he plans to use a coherent-based approach to blend with what Verizon is doing in the long haul. But given the interest in 4x25G approaches, it’s likely that carriers will prove as diverse in their technology selections as their systems suppliers.

作者: stupid 时间: 2012-3-29 13:33
标题: OFC上的100G 光模块
Line side, client side, it didn’t matter – it seemed every optical module vendor at OFC/NFOEC 2012 in Los Angeles had some sort of story to tell about their work at 100 Gbps. This Reporter’s Notebook focuses on the line side.

Going into the show, three module vendors had promised to have 100-Gbps modules based on dual-polarization quadrature phase-shift keying (DP-QPSK) and coherent detection ready for sampling in the first half of this year. All three appear to be on target.

Opnext (NASDAQ: OPXT), in fact, began shipping samples at the beginning of this year, as Chairman, President, and CEO Harry Bosco revealed at the company’s last quarterly earnings call. Six customers from around the world have received either the OTM-100 module or the OTS-100FLX subsystem suite, the company announced, with South American systems house Padtec S/A raising its hand as one of the subsystem recipients. The suite includes the OTS-100MXP 10x10-Gbps muxponder, the OTS-100TXP transponder, and the OTS-100RGN universal regenerator. Eight of the line cards fit into Opnext’s OTS-4000 chassis, and two will go in the company’s recently released 4RU high OTS-mini shelf.

Bosco said at the show that the company has shipped about 20 samples to the six customers, with 30 more samples on their way out the door – some going to new customers beyond the existing six. He said he expects the modules will prove most popular with Tier 1 and 2 systems suppliers, with the subsystems holding the most appeal with smaller customers. Both the modules and the subsystems benefit from soft-decision FEC.

Oclaro (NASDAQ: OCLR) chose to talk more about how its MI 8000XM 100-Gbps coherent module is being made rather than its delivery – although Terry Unter, president and general manager of the Oclaro Optical Networks Solutions Business Unit, confirmed to me that the module is on schedule to begin sampling in the first half of this year. Having focused on supplying 100-Gbps optical components first, Oclaro says it now has the ability to meet its optical component requirements for the MI 8000XM in-house. The high-speed electronics, of course, still come from an outside source (NTT/NEL); the company has second sources lined up for the optical bits as well.

I didn’t have a chance to visit with the third vendor, Fujitsu Optical Components. However, the company demonstrated its module in the booth and appears to remain on track to begin sample deliveries in April, as previously announced.

I did visit with Finisar (NASDAQ: FNSR), however, which unveiled a prototype of its own 100G coherent module. It also integrates soft-decision FEC to enable reaches of up to 2000 km. Executive Chairman Jerry Rawls told me that the module is now undergoing a power-reduction effort and awaiting the next generation of NTT/NEL’s DSP technology. He said he expects to begin shipping modules during the first quarter of 2013. However, Rafik Ward, vice president of marketing, was more optimistic, saying later in the show that he expects production to start by the end of the year.

Not surprisingly, JDSU (NASDAQ: JDSU and TSX: JDU) also plans to follow up its newly announced 40-Gbps coherent module with a 100-Gbps version. Sinclair Vass, senior director of marketing within the Communications and Commercial Optical Products Business Segment, said he expects the module will begin sampling either late this year or early in 2013 as well.
[UPDATE] Something of a wild card in this deck of 100G module suppliers is Acacia Communications. The startup is easing its way out of stealth mode. While I didn't have a chance to talk to anyone at the company directly, Raj Shanmugaraj, president and CEO, told attendees at the OSA Executive Forum that his company has been shipping devices for 9 months to several customers, for a combination of trials and deployments.

Meanwhile, the folks at EMCORE (NASDAQ: EMKR), who have had success selling their narrow-linewidth lasers for 100G coherent applications, admitted that they’ve at least considered the idea of building their own module, but didn’t indicate that they had decided to make the leap. NeoPhotonics, who also has supplied ITLA technology for 100G coherent, currently has no plans to jump into the long-haul coherent module market. It sounded like a metro-focused module might be more tempting, however.

Speaking of the metro, while DP-QPSK with coherent detection is the preferred approach for long-haul applications, faith in its cost-effectiveness for metro applications isn’t as strong (see “Metro 100G: An OFC/NFOEC Reporter's Notebook”). Therefore, direct-detect transmission is getting a serious look, particularly in the form of 4x28-Gbps technology.

Oclaro was first out of the gate with a product announcement in this area. The new CFP transceiver uses a direct-detect optical duobinary (ODB) modulation format. It should begin sampling by the middle of this year, with a production launch scheduled for year’s end. The four wavelengths may be tuned individually or as a group. Oclaro plans to add MLSE capability to extend reach, although company sources declined to say when.

Finisar also showed off its tunable CFP 4x28G offering based on ODB. Like the Oclaro device, Finisar’s module sports eight fibers (four for transmit, four for receive). Unlike its competitor, however, Finisar also plans to offer a companion pizza box called SpectraWave that will provide multiplexing/demultiplexing and amplification for the four wavelengths. According to Rafik Ward, the CFP should support reaches as long as 400 to 600 km. He expects both the CFP and the companion SpectraWave box to be in production by the fourth quarter of this year.

Oclaro and Finisar won’t have the market to themselves, however. Vendors who confirmed that they also have 4x28G modules in development include the Israeli startup Effdon, EMCORE, JDSU, and Opnext.

作者: qingdalj 时间: 2015-10-21 17:03
看英文好吃力呀

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