Teleste White Paper On Barrier Technology

Transcript

White paper BarrIER® technology BarrIER® - Benefits and implementation of ingress/egress reduction A major topic for cable operators is the battle for adequate carrier-to-noise levels to ensure that upstream modulation schemes can operate in an error-free manner. Ongoing migration to higher transmission frequencies with DOCSIS 3.1 and better modulation schemes to support the growing capacity issues, for example 16 QAM to 256 QAM and even to 1024 QAM, will further increase operators’ need to control ingress/ egress in their networks, enhance C/N performance and maintain service reliability. e challenge is that most of the network noise come from within customers’ homes, a domain where operators have little or no control. BarrIER® technology is an innovative solution for reducing ingress/egress that addresses the complete in-home interconnect domain and solves the problem of maintaining adequate C/N levels. Using BarrIER® will reduce the need for manual maintenance work, greatly reduce operational costs, and incrementally increase service reliability and enhance network performance. Ingress/egress in networks As bi-directional systems, cable networks are vulnerable to interference from outside signals, which can harm the quality of digital services. Interference results in added noise and disrupts the desired signal, thereby leading to poor network “health.” High fault rates that are difficult to rectify, for instance slow Internet browsing speeds, loss of connection, poor interactivity, and the slow speed of VOD (Video on Demand) services, will all result in a poor customer experience and be costly for the operator to rectify. Defined as any undesired emission of signals in a communication circuit, two types of interference and noise can be identified in HFC networks. Ingress is noise that is filtered back to the network from home, whereas egress is noise that comes from RF signals filtered from the network into the home. Egress noise is becoming an increasingly important issue as governments are starting to clamp down on in-home interference signals that could prevent potential new services or interfere with current products or services. Today, cable operators already have a legal obligation to control the amount of noise they potentially radiate within a home or external plant from open or loose connectors and cabling. As a means of characterizing the condition and health of their networks, cable broadband operators routinely measure the carrier-to-noise ratio (CNR); CNR is a measure of the received carrier’s strength relative to the strength of the received noise. High CNR allows the upstream and downstream signals to operate at full capacity, providing optimum two-way data speeds and a trouble-free digital TV experience. It is fair to say that to maintain optimum service reliability and face the challenge set by Telco and satellite service providers, adequate CNR has become a mainstay issue for cable broadband operators. Growing demand for more noise resilience and network reliability With the upcoming new standards and technologies, content delivery will need to take into account new radio frequencies. e DOCSIS® Radio Frequency Interface Specification includes a minimum CNR parameter for data signals in its assumed RF channel transmission characteristics. Introducing approximately 25 kHz to 50 kHz wide carriers, the upcoming DOCSIS 3.1 will multiply the number of carriers to thousands through the use of OFDM (Orthogonal Frequency-Division Multiplexing) and also increase transmission capacity considerably from 256 QAM to 1024 QAM - or more for forward path transmission. To achieve higher noise resilience and make it possible to operate at a higher level of modulation, the DOCSIS 3.1 includes a method of forward error correction (FEC), called a low- density parity check (LDPC). However, FEC alone cannot solve the problem of maintaining a stable CRN. Currently, a transmission capacity of 256 QAM requires a CNR of 25 dB. Maintaining such a transmission capacity will be a major challenge. A transmission capacity of 1024 QAM would require the CRN to exceed 35 dB, which in practice means that maintaining a stable CNR will become more and more of a major challenge and quite expensive. Also, the problem of noise during return path transmission still needs to be solved. Another important topic for cable operators is the upcoming 4G LTE (Long Term Evolution) wireless service, which operates at a higher RF level in the 700–862 MHz band, which in turn lies within the cable television band at a range of 5–862 MHz. LTE can also be used at up to 1200 MHz. It will eventually be used by CATV operators for the forthcoming DOCSIS 3.1. To prevent interference caused by 4G LTE, many operators are pushing for higher RFI (Radio Frequency Interference) to better screen for effectiveness and noise resilience in their components. To help operators achieve the goal, the main governing body, the European Committee for Electrotechnical Standardization (CENELEC), has now complemented its EN50083-2 Cenelec Class A standard with Class A+ and Class A++ standards, with Class A + adding an additional 10 dB on to Class A and an additional 20 dB to Class A++. Frequency range (MHz) Cenelec Class A limit value (dB) 5 to 30 85 30 to 300 85 300 to 470 80 470 to 950 75 950 to 3000 55 Limits of screening effectiveness for passive equipment within the nominal frequency ranges In theory, implementing the new standards and adhering to the higher RFI figures should mean that operators will have fewer noise issues. So why do all operators who work so hard to specify and purchase such highly detailed network components — passive and active products, cable products, and connector products — still have major noise issues in their networks? All of the above issues come down to one thing: the effectiveness of the RFI screening for all of the in-home interconnect and associated components. A problem on the wrong side of the front door e key for achieving higher RFI screening effectiveness lies in consumers’ homes: more than 90% of all related noise issues within a cable plant occur as a result of noise coming from within the home, where loose connectors, open F female and F male connectors, active in-home distribution amplifiers, and poor installation jobs are the major sources of noise. For operators, the problem is that they have little or no control over home environments and their customers’ own installation jobs. And what is more, solving noise problems inside homes requires a great deal of manual on-site work, and thus results in increased operational expenses. Experiences from the field show that six out of every ten homes with noise issues will require at least three visits before field technicians gain entry to the site. It is then nearly impossible to identify all of the sources of ingress, so the technician will simply redo all of the connections, change out all passive products (isolators, splitters, and cables), test the system, and leave. As a result of the ambiguity and unpredictability of home environments, solving noise issues is time consuming and customers’ homes are often left connected to the cable network even if they churn. e challenge of fighting noise problems within a home environment is further compounded by the fact that before sending out technicians operators first need to choose which households to visit from among thousands and even tens of thousands of customers. Despite these problems, fighting noise is essential for cable operators if they want to remain competitive and new tools for detecting, locating, and resolving the problems are already available. e planned use of 700 MHz LTE for government and public safety applications will put additional pressure on maintaining service reliability and underscore the importance and urgency of resolving noise issues. Ingress/egress mitigation - BarrIER® ingress/egress reduction BarrIER® ingress/egress reduction is a technology that provides broadband cable operators with a solution for ingress and egress issues within in-home networks. It prevents LTE and return-path noise from entering the cable television network via loose and open ports. BarrIER® addresses the complete in-home interconnect domain with the aim of permanently fixing potential sources of ingress/egress due to loose connectors, open F female and F male ports, active products, such as home distribution amplifiers, and poor installation jobs. e technology can be incorporated into new products, such as, isolators, amplifiers, flyleads, wall outlets, splitters, taps, and anything else that is under threat of being left wide open due to in-home disconnects or simply unused connections. e BarrIER® technology works by stopping noise from entering or exiting an in- home network with a more than 40 dB signal attenuation over the whole radio frequency spectrum of 5–2400 MHz. e technology automatically creates RF screening on open connectors and prevents loose connectors from occurring, thus making the network quality independent of consumer behavior. BarrIER® features • Reduces customer churn and increases service reliability. • • Benefits for the end-customer: • Includes a mechanism that automatically disconnects from the network when the connection is not in use. Once fitted, BarrIER® is permanent. Reduces ingress and egress into open F female splices and ports, as well as unused F male connectors. • Up to 40 dB of ingress reduction at all in-home interconnect points, providing incremental network C/N improvements as more and more BarrIER® features are deployed. Also, frequency spectrums that were previously unusable due to noise will incrementally become more usable over time as C/N levels improve. • Improved RFI screening of loose connectors: e BarrIER® technology puts a constant force on the F male and F female connectors, preventing the connectors from coming loose. In the event of a poor installation job, where a connector has not been tightened correctly, the push force from the BarrIER®connector will push the mating connector back on to its threads, thus enhancing the grounding connection and further improving ingress/egress by up to an additional 20 dB compared to the current standard continuity connectors. • Protects the network from 4G/LTE: e BarrIER® technology is effective over the full 5–2400 MHz spectrum, so cable services are protected against 4G/ LTE ingress. BarrIER® will also prevent high-level RF signal egress from entering the cable network and potentially interfering with 4G/LTE equipment within the home. • Available on any female/male connector or port, including splices, splitters, taps, amplifiers, filters, flyleads, and OEM F connectors for equipment such as set-top boxes. − Uninterrupted and reliable services − Faster broadband − Seamless working of 4F/LTE mobiles BarrIER® benefits • Closes the last problem area for CATV operators struggling to maintain network performance due to noise issues emanating from the home. • Reduces network maintenance costs and OPEX by cutting down on the need for ongoing manual maintenance at a customer’s premises and closing the in-home interconnect permanently. • Allows more effective use of the return path spectrum • Incrementally frees up previously unusable frequency spectrum, as BarrIER® is deployed by improving network CNR. • Enables operators to disconnect customers without exposing the network to ingress and egress, thus putting the operator back in control. • Allows operators to develop self-install solutions, as there is no need to perform difficult disconnects to solve the churn issue. • Reduces greatly the impact of LTE/4G services launched in the CATV band. BarrIER® home installation Putting BarrIER® to the test: RFI screening e following RFI screening results demonstrate how BarrIER® can fix the following noise issues: Testing on open F female ports and F male connectors • Open F female connectors • Open F male connectors • Loose connectors • Active in-home distribution amplifiers • Poor installation In the home environment, open F female ports are primarily associated with in-home splitters, home distribution amplifiers, and galvanic isolators. e most common female connector is in a wall outlet. F Male connectors are attached to a coaxial cable, which is then connected to a piece of hardware. When disconnected, the hardware can have one or more exposed, unshielded electrical terminals. An open F connector is by far the worst example of noise ingress and egress due to the fact that the center conductor of an F male connector acts as a high-gain dipole antenna. RFI screening for system noise floor and terminated connection in a typical test set-up Green trace describing the system noise floor. Blue reference lines = Cenelec Class A limits. Terminated connection. Terminating the connection drops noise to the floor level. Red trace = system noise floor Green trace = actual measurement Blue reference lines = Cenelec Class A limits RFI screening for open unterminated F female port without BarriER Two-way splitter, one port open Red trace = system noise floor Green trace = actual measurement Blue reference lines = Cenelec Class A limits RFI screening for open unterminated F female port with BarrIER® Two-way splitter with BarrIER® RFI screening for system noise floor and open F male port without BarrIER® Standard F male Red trace = system noise floor Green trace = actual measurement Blue reference lines = Cenelec Class A limits RFI screening for system noise floor and open F male port with BarrIER® BarrIER® F male RFI screening for HDU amplifier with 4 output ports In-home amplifier, all ports terminated Red trace = system noise floor Green trace = actual measurement Blue reference lines = Cenelec Class A limits In-home amplifier, ports open Red trace = system noise floor Green trace = actual measurement Blue reference lines = Cenelec Class A limits In-home amplifier with BarrIER® Testing on open ports clearly shows that all open ports seriously degrade the effectiveness of RFI screening on any device. With BarrIER® technology, all open ports still remain within Cenelec Class A screening effectiveness limits, yet they operate as a normal connector when connected to a mating connection. Preventing 4G LTE interference Detailed LTE testing was done using the latest state-ofthe-art set-top boxes and a cable modem. e testing was done using a world-leading EMC test facility in the UK. Test regime in a nutshell • Test carried out at a world-leading EMC test lab • Testing carried out on the latest state-of-the-art digital set-top box and cable modem • Video transport stream DVB-C 256 QAM • LTE carrier 64 QAM OFDMA, 20 MHz bandwidth with 1200 sub-carriers • LTE power measured on a 3D Optical power head • Testing done at a range of 600–904 MHz in 8 MHz steps • Unique automated test set-up using a set-top box and cable modem to provide real-time data − Pre-errors − Post-errors − SNR − MER e LTE carrier was transmitted in a calibrated RF chamber and all key RF electrical parameters from the set-top box were measured. e testing was done at a range of 600–904 MHz in 8 MHz steps and the following parameters were measured. • SNR/MER • Pre-bit error rate/Post-bit error rate • QAM carrier’s RF input level set to STB • LTE field strength (measured using an optical 3D power head) e first test was done on a standard, F male, RF flylead, one end of which was connected to a two-way splitter and the other end left unconnected. e LTE signal was increased until both the pre- and post-error bit rate data began to corrupt the video signal. e corrupted video signal was observed using an LTE field strength of only 0.3 V/M! Using exactly the same equipment configuration, but substituting the unconnected, standard F male connector with a BarrIER® F male connector, the flylead configuration withstood a massive LTE signal field strength of 17 V/M without a single error during the signal transmission. − Input power level dBmV − LTE field strength V/m (using a 3D Optical power head) Testing on open F male connectors using set-top box Recent lab testing using a state-of-the-art digital set-top box running an HD video transport stream DVB-C 256 QAM while transmitting a fully loaded LTE carrier (64 QAM OFDMA, 20 MHz bandwidth with 1200 sub-carriers). e LTE testing showed that a field strength of 0.2 V/M affected an open F male connection, removing the STB. With BarrIER®, there was no adverse effect from LTE with a field strength of 17 V/M. A typical LTE base station can produce up to 5 V/M and a hand set 1 V/M, so it is clear that BarrIER® will completely protect all open connections against LTE. Test summary for open standard F male connector As can be seen, the set-top box experienced catastrophic failure with an LTE field strength of only 0.2/0.3 V/M. is can be further seen where the STB went out of lock, the MER degraded, and uncorrectable errors increased significantly. Test summary for open F male connector with BarrIER® As can be seen, the set-top box experienced no LTE interference, even with a field strength reaching 17V/M with an open BarrIER® F male connector on the end of the RF flylead. Conclusions Maintaining good RFI screening within a home environment results in controlled ingress and egress. e RFI screening reference is dictated by the industry standard (Cenelec), which is used worldwide by all cable operators as their reference for acceptable RFI screening of in-home products. We can clearly see that there are serious screening issues with any type of loose/open connection within the home. However, making an open connection with BarrIER® technology provides an improvement of up to 40 dB in RFI screening over any standard open connector/ connection. e end result is that even an active HDU amplifier with unity gain and all open ports will maintain Cenelec Class A screening. An additional benefit of BarrIER® is that deploying it can eliminate the open connection issues and result in incremental improvements of the network C/N. is is essential for the rollout of 256 QAM and the ongoing modulation schemes heading to 1024 QAM, which in turn will require even lower C/N levels. e requirement can be achieved via segmentation; however, this solution is impractical and costly. e BarrIER® F male and female connectors improve loose connection RFI leakage by approximately 20 dB compared to all current types of connectors. By design, BarrIER® puts pressure on the mating connector thread, thus preventing the male connector from turning or coming loose. If every open or loose F port was closed, then the ingress/egress issues from within the home would be nominal; BarrIER® can be used to close all open ports permanently. Every cable operator is struggling to maintain adequate network C/N in their upstream. It is a battle to try to maintain any C/N headroom. Field technician teams are working on the network using RF sniffer equipment to identify leaks and entering homes to carry out connectorization maintenance, which in most cases means that the operator will throw away its original investment, such as splitters, isolators, or connectors. MDU applications and student accommodations are another major issue involving constant open ports, reconnections, and disconnections. Summary e bare minimum of RFI screening effectiveness for all in-home interconnect solutions needs to meet at least Cenelec Class A criteria. A poor RF interconnect within the home produces serious ingress and egress issues, and open connections of any type can produce catastrophic network problems. Ingress is not the result of a single home producing ingress noise, but rather the culmination of many homes in a nodal area producing a summation of noise build-up, which eventually affects the overall upstream and in some cases the downstream performance of a cable network. Impulse noise from a single open connection can take down a complete nodal area on its own, and it can be very difficult to locate, as impulse noise generally is short-term, and when gone, cannot be detected until it appears again, which is usually unpredictable. When connections are good, it is clear that the number of noise issues is low and under control. However, due to the unpredictability of in- home environments, this scenario does not exist today. Operators need to provide their customers with quick access to network services, but this requires an existing open connection, which is a recipe for disaster in terms of RFI screening, 4G LTE, and overall noise mitigation, including both ingress and egress. At the same time, cable service providers have a legal obligation to control egress in their networks. e BarrIER® technology is a simple, cost-effective way to permanently solve problems created by noise. e technology allows for open ports, improves loose port screening, and will enhance the overall quality of services provided to the customer. Teleste is an international technology company that develops and offers video and broadband technologies and related services. Our supply of technology contributes to the convenience and safety of daily living. Our core business is video - image and data processing, transfer and management. Our customer base consists of cable and telecom operators, as well as public sector organizations. Our business is divided into two divisions, which are Video and Broadband Solutions and Network Services. In both areas, we rank among the world’s leading companies and technological forerunners. Video and Broadband Solutions focuses on access networks and product solutions in video surveillance applications. Network Services offers comprehensive services for network design, construction and maintenance. In 2013, Teleste’s net sales totalled EUR 192.8 million, and the company employed about 1,300 people. Teleste runs a worldwide network of offices and more than 90% of its sales are generated outside of Finland. e Teleste Corporation P.O.Box 323, FI-20101 Turku, Finland Phone: +358 (0)2 2605 611 Fax: +358 (0)2 2446 928 [email protected] www.teleste.com P3I_ BarrIER® Technology © 2014 Teleste Corporation. All rights reserved. TELESTE is a registered trademark of Teleste Corporation. company is listed on the NASDAQ OMX Helsinki Ltd. For more information see www.teleste.com and follow @telestecorp on Twitter.