Networks are increasing in their complexity, both in terms of cascaded filtering (e.g., via ROADMs in mesh networks) and multiple-bit/symbol modulation formats. For instance, intra-channel noise will increasingly be spectrally carved by filters, the signal bandwidths will frequently be as large as the effective channels widths, and different data rates will be used more and more on a given network. All these factors will affect wavelengths differently, as some wavelengths might have passed through a different number of ROADMs, data rates in a single fiber might vary from one wavelength to the next, etc. Nevertheless, OSNR remains a critical network performance parameter, which requires OSNR measurements optimized on a per-channel basis, like the WDM-aware technique. Purely polarization-based OSNR measurement techniques (e.g., polarization nulling) can perform well when networks and noise sources remain simple, but as demonstrated herein, the robustness and performance of WDM-aware measurement renders it well suited for advanced network architectures and modulation formats.

Having developed for twenty years, the digital subscriber line (DSL) technology has become the mainstream access technology in the telecommunications field. The DSL technology keeps developing to meet requirements for higher bandwidth, showing great marketing potential. The latest Vectored DSL technologies defined in the ITU-T Recommendation G 993.5 have the ability to cancel crosstalk between neighboring twisted-pairs and provide channel bandwidth of 100 Mbps based on VDSL2 using 30a bandplan. By combining channel expansion, crosstalk cancellation and multi-pair bonding based on the Vectored DSL and MIMO DSL, the SuperMIMO technology dramatically increases the DSL access rate because of extra virtual channels and a near crosstalk-free environment. The laboratory test results show that SuperMIMO helps achieve a downstream rate of over 300 Mbps by using two twisted pairs and of 700 Mbps by using four twisted pairs. SuperMIMO prolongs the life of twisted pair cable by increasing the access bandwidth. 

In this white paper, you will learn how the coherent lightwave signal analysis methodologies utilize the high speed A to D of an oscilloscope to enable access to a complete set of measurement outputs, including bit error rate (BER) results, for better characterization of complex optical signals on fiber and evaluation of long-haul telecommunications systems performance. By combining channel expansion, crosstalk cancellation and multi-pair bonding based on the Vectored DSL and MIMO DSL, the SuperMIMO technology dramatically increases the DSL access rate because of extra virtual channels and a near crosstalk-free environment. The laboratory test results show that SuperMIMO helps achieve a downstream rate of over 300 Mbps by using two twisted pairs and of 700 Mbps by using four twisted pairs. SuperMIMO prolongs the life of twisted pair cable by increasing the access bandwidth.