Submarine network technology specialist Xtera filed a complaint with the U.S. International Trade Commission (ITC) on December 22, 2017, that alleges Nokia, its wholly owned subsidiary Alcatel-Lucent Submarine Networks (ASN), and NEC Corp. and associated affiliates have infringed on five of Xtera's patents. At issue are submarine network equipment as well as Nokia's Photonic Service Engine 2, a key component of Nokia's current coherent optical transport equipment (see "Nokia upgrades 1830 PSS packet-optical transport family with new coherent chipsets, improved multi-rate performance"). Xtera asks that the ITC ban the accused companies from selling or importing into the U.S. products and technology named in the complaint.
None of the accused companies have issued public responses. Nokia, ASN, and NEC America had not responded to Lightwave requests for comment at the time this article was posted. As responses are received, this article will be updated.
The five Xtera patents at the heart of the complaint include:
- Patent 8,380,068, "Distinct Dispersion Compensation for Coherent Channels" (2013), which describes a technique by which coherent channels can receive different dispersion compensation treatment than non-coherent channels
- Patent 7,860,403, "Data Format for High Bit Rate WDM Transmission" (2010), which describes a method of encoding data to improve spectral efficiency in WDM systems that enables efficient transmission of high-bit-rate signals
- Patent 8,971,171, "Reduced FEC Overhead in an Optical Transmission System" (2015), which describes a means of dividing an encoded sequence between two or more channels to reduce bit rate per channel
- Patent 8,351,798, "Phase Shift Keyed High Speed Signaling" (2013), which describes a way to address dispersion when minimum accumulated distortion is caused to occur halfway down a long-haul link that Xtera's complaint says may improve performance
- Patent 8,406,637, "Automatic Pre-Emphasis" (2013), which covers a pre-emphasis approach in which a centralized signal is applied to one or more transmitters in a given band to maintain an average drive power in the band; complementary band gain amplifiers compensate for the centralized signal's effect.
Xtera claims that Nokia's Photonic Service Engine 2 Coherent Technology and 1620LM Submarine Line Terminal Equipment infringe on one or more of the patents. In the case of NEC, the company's NS Series Submarine Repeatered Subsea Systems are at issue.
The Xtera complaint alleges the company approached Nokia with an offer to license use of the patents' intellectual property, which Nokia declined. Xtera does not appear to have made a similar offer to NEC.
The ITC has yet to institute an investigation into Xtera's claims. A formal evidentiary hearing also has not yet been scheduled. The petition has been assigned Docket Number 3283.
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