Most Popular Articles

• ARM’s new CPU and GPU will power mobile VR in 2017

  May 30, 2016 by Telecom News / 609 Views

  

   

  
  

  ARM, the company that designs the processor architectures used in virtually all mobile devices on the market, has used Computex Taipei 2016 to announce new products that it expects to see deployed in high-end phones next year. The Cortex-A73 CPU and Mali-G71 GPU are designed to increase performance and power efficiency, with a particular view to supporting mobile VR.

  ARM says that its Mali line of GPUs are the most widely used in the world, with over 750 million shipped in 2015. The new Mali-G71 is the first to use the company's third-generation architecture, known as Bifrost. The core allows for 50 percent higher graphics performance, 20 percent better power efficiency, and 40 percent more performance per square mm over ARM's previous Mali GPU. With scaling up to 32 shader cores, ARM says the Mali-G71 can match discrete laptop GPUs like Nvidia's GTX 940M. It's also been designed around the specific problems thrown up by VR, supporting features like 4K resolution, a 120Hz refresh rate, and 4ms graphics pipeline latency.

   

  As for CPUs, ARM is announcing the new Cortex-A73 core, which prioritizes power efficiency. It's up to 30 percent more efficient than the previous Cortex-A72 while offering about 1.3 times the level of peak performance, but ARM has also focused on sustained usage — the A73 offers over twice the performance within its power budget, meaning it doesn't need to be as hasty to slow down to save battery life.

   

  

   

  Although ARM architecture dominates the mobile landscape, there's a good chance you won't see these specific products in your 2017 flagship phone. ARM licenses its architecture and cores separately, meaning companies are free to pick and choose what they like. Apple, for example, licenses ARM architecture but now designs its own custom CPU cores (known as Twister in the most recent A9 processor) and uses PowerVR GPU solutions from Imagination Technologies. Samsung, meanwhile, designs some Exynos processor cores but uses them alongside ARM's Cortex cores and Mali GPU in the international Galaxy S7. And Qualcomm reverted to its own custom Kryo CPU cores in the Snapdragon 820 — which powers the US Galaxy S7 — after using Cortex in the 810.

  All of this is to say that you shouldn't take the performance laid out here by ARM as a benchmark for your next phone, because it'll all depend on how the manufacturers choose to implement the technology. But the new Cortex and Mali products do demonstrate that mobile technology continues to advance in terms of power and efficiency, and that it's adapting to new challenges such as VR.

  ARM expects chips to move into production at the end of the year and appear in shipping devices in early 2017.

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• Ethernet Passive Optical Network Tutorial

  Feb 8, 2016 by Articles / 607 Views

  EPON is a PON-based network that carries data traffic encapsulated in Ethernet frames. Unlike other PON technologies which are based on the ATM standard, it uses a standard 8b/10b line coding and operates at standard Ethernet speed. This lets you utilize the economies-of-scale of Ethernet, and provides simple, easy-to-manage connectivity to Ethernet-based, IP equipment, both at the customer premises and at the central office.

  EPON Network Structure

  A typical EPON system is composed of OLT, ONU, and ODN (Figure 1).

  

  Figure 1. EPON Network Structure

  The OLT（Optical Line Terminal）resides in the Central Office (CO) and connects the optical network to the metropolitan-area network or wide-area network, also known as the backbone or long-haul network. OLT is both a switch or router and a multi-service platform which provides EPON-oriented optical interfaces. Besides the network assembling and access functions, OLT could also perform bandwidth assignments, network security and management configurations according to the customers’ different QoS/SLA requirements.

  The ONU（Optical Network Unit）is located either at the end-user location or at the curb and provides optical interfaces which are connected to the OLT and service interfaces at users’ side such as voice, data and video.

  The ODN（Optical Distributed Network）is an optical distribution network and is mainly composed of one or more passive optical splitters which connects the OLT and ONU. Its function is to split downstream signal from one fiber into several fibers and combine optical upstream signals from multiple fibers into one. Optical splitter is a simple device which needs no power and could work in an all-weather environment. The typical splitters have a splitting ratio of 2, 4, 8, 16 or 32 and be connected to each other. The longest distance the ODN could cover is 20 km.

  EPON Downlink and Uplink Technology

  In an EPON the process of transmitting data downstream from the OLT to multiple ONUs is fundamentally different from transmitting data upstream from multiple ONUs to the OLT.

  In the downstream direction, Ethernet frames transmitted by the OLT pass through a 1:N passive splitter and reach each ONU. N is typically between 4 and 64. This behavior is similar to a shared-medium network. Because Ethernet is broadcast by nature, in the downstream direction (from network to user), it fits perfectly with the Ethernet PON architecture: packets are broadcast by the OLT and extracted by their destination ONU based on the media-access control (MAC) address (Figure 2).

  
  Figure 2. Downstream Traffic in EPON

  In the upstream direction, due to the directional properties of a passive optical combiner, data frames from any ONU will only reach the OLT, and not other ONUs. In that sense, in the upstream direction, the behavior of EPON is similar to that of a point-to-point architecture. However, unlike in a true point-to-point network, in EPON data frames from different ONUs transmitted simultaneously still may collide. Thus, in the upstream direction (from users to 13 network) the ONUs need to employ some arbitration mechanism to avoid data collisions and fairly share the fiber-channel capacity (Figure 3).

  
  Figure 3. Upstream Traffic in EPON

  EPON and ADSL Comparison

  The requirement of bandwidth is increasing crazily with the incoming of digital age. Therefore the current high speed copper cable ADSL (Asymmetric Digital Subscriber Line) cannot meet our needs longer. The bandwidth of ADSL is limited to only a few megabit per second and the upstream and downstream bandwidth are not equal either. However, optical fiber has larger bandwidth and superior transmission capability which reaches gigabit per second. Hence, optical fiber used in access network is the future trend. And since Ethernet is low cost, uncomplicated widely-used in current network, and its application is very popular nowadays. So it is not hard to see that it is feasible and economical to combine them together. EPON technology combines a mature Ethernet technology and high-bandwidth PON technology, which is an ideal access method to achieve integrated services. In the future, highbandwidth business will surely drive up existing EPON which has the rate of 1.25Gbps in both the downstream and upstream directions.

  EPON Technical Advantages

  EPONs are simpler, more efficient, and less expensive than alternate multiservice access solutions. Key advantages of EPONs include the following:

  Higher bandwidth: up to 1.25 Gbps symmetric Ethernet bandwidthLower costs: lower up-front capital equipment and ongoing operational costsMore revenue: broad range of flexible service offerings means higher revenues

   

  With the growing of EPON technology, interaction standards and EPON devices, EPON has entered the large scale application phase driven by the huge market demands. EPON is fit for the access market which is at the end of the fibers and which has a certain density and these markets include FTTH, FTTP, FTTB, FTTN etc.

  EPON becomes a very economical and effective broadband access solution because of its predominance in equipment investment and also the operations, maintenance and etc. It could be said that the EPON technology has become the developing direction of access network’s technologies in the future as an ideal solution for FTTH.

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• Huawei Completes 5G Key Technology Tests in the Field Trial Sponsored by IMT-2020 5G Promotion Group

  May 30, 2016 by Telecom News / 596 Views

  [Shenzhen, China, May 27, 2016] Huawei completed the first phase of key 5G technology tests as a part of a series field trials defined by the IMT-2020 5G Promotion Group. In April 2016, the outdoor macro-cell tests, conducted in Chendu, China, consist of a number of the foundational key enabling technologies and an integrated 5G air-interface. The test results successfully demonstrated that the new 5G air interface technology can effectively improve spectrum efficiency and to meet diverse service requirements for 5G defined by ITU-R.

  
  Huawei completes 5G key technology tests in 5G field trial

  Strong Promotion for Global Partnership on 5G Technology Innovation and a Global 5G Standard

  Launched by China Academy of Information and Communication Technology (CAICT), the IMT-2020 5G Promotion Group aims to foster a joint effort to promote 5G technology evaluation and field test among the global mobile industry and ecosystem to ensure the successful commercial deployment by 2020. One of the key objectives for IMT-2020 5G Promotion Group is to realize the 5G vision for the enhanced mobile broadband service as well as to create the new capabilities for 5G to enable the IoT and vertical services, this represents the unprecedented technical challenges such as to realize 10Gbps or peak rate 20Gbps user data rate, 100 billion connections, and 1 ms of end-to-end network latency for the 5G air interface.

  Early this year, IMT-2020 5G Promotion Group announced a three phase 5G networks trial plan, spanning from 2016 to 2018, with a first phase test from September 2015 to September 2016. The first phase test is focused on key radio technologies and performance test.

  As one of the core members in the IMT-2020 5G Promotion Group, Huawei actively contributed IMT-2020 5G Promotion Group and 5G technology test. In addition, Huawei established an extensive collaboration with CAICT, China Mobile, China Unicom, and China Telecom in the Chinese operator community to explore the innovative air-interface technologies to achieve best spectral efficiency and massive links capabilities. Huawei’s effort is focused on New Radio (NR) technology, which includes the optimized new air-interface, full-duplex and massive MIMO technologies, these are the enabling technologies to achieve the superior end-user experience for the emerging mobile broadband service such as 4K, 8K and virtual reality and augmented reality.

  Best-in-Class Test Results Using 5G New Air Interface

  The 5G air interface technology has been implemented through three novel foundational technologies, i.e., filtered Orthogonal Frequency Division Multiplexing (F-OFDM), Sparse Code Multiple Access (SCMA) and Polar code to meet 5G requirements and performance targets.

  F-OFDM technology is the basis for creating ultra-flexible air-interface to adaptively fit all the 5G use-case scenarios defined by ITU-R with a single radio technology platform. It allows multiple concurrent radio numerologies and frame structure to deliver very diverse services; F-OFDM can ensure the future-proof for the 5G system to meet emerging innovative services requirements. The test results showed that F-OFDM can increase system throughput by 10% using those free guard bands in LTE system. In addition, F-OFDM supports asynchronous transmission from different users. Test results showed that it will provide 100% higher system throughput compared with that in LTE system in the presence of mixed service on the same carrier frequency with mixed radio numerologies. .

  SCMA is to support massive connections and obtain higher system throughput simultaneously via the joint optimization on sparse SCMA codebook design and multi-dimensional modulation. It can further consider optimization on power allocation among different SCMA layers especially in downlink to improve total system throughput. The test results showed that SCMA is to increase the uplink connection number by 300% and at the same time increased the downlink system throughput up to 80%.

  For Polar code, it allocates information to the highly reliable data locations in the code structure to transmit useful information of user and at the same time it supports channel coding of any code rate with an appropriate code construction to fit any future service requirements. The test results showed that Polar code provided coding gain from 0.5dB to 2.0dB compared with Turbo code used in LTE system.

  System Integration of Innovative 5G Air Interface Technologies

  The flexible system integration of several innovative 5G air-interface technologies, namely, F-OFDM, SCMA and massive MIMO has been verified in the first phase of key 5G technology tests. In the test, multi-user MIMO (MU-MIMO) supported up to 24 users and up to 24 parallel layers transmission on the same time-frequency resources. The test results showed that MU-MIMO can achieve 3.6Gbps cell average throughput using 100MHz system bandwidth, it is almost 10 times of that in LTE baseline system.

  The trial has validated the optimal integration of the above new radio technologies and the capability of flexible 5G air-interface technologies, the trial is also served as a technical re-risk to support the on-going 3GPP standardization work.

  Full Duplex Implemented in the First Phase of 5G Test

  Full Duplex mode has also been tested in the first phase of 5G test. In the initial test stage on Full Duplex, it allows simultaneous transmitting and receiving of data at the base station with three level cascaded technologies, namely, passive analog cancellation, active analog cancellation, and digital cancellation. The test results showed that the Full Duplex can provide self-interference cancellation capability more than 113dB in real world environment and result in a total 90% system throughput gain over the conventional half duplex mode used today.

  Huawei has successfully completed the first phase test of 5G technologies in China. "The trial of 5G technologies in China will be a great contribution to 5G applications in the future.” Dr. Wen Tong, Huawei 5G Chief Scientist emphasized that, "As a member of the IMT-2020 5G Promotion Group, Huawei is pleased to work with CAICT, China Mobile, China Unicom, and China Telecom, and took the initiative to be the first to complete 5G key technologies tests and corresponding system integration test based on our proposed 5G new air interface."

  He also announced the plan of the second phase of 5G test which will focus mainly on the wide coverage, high hotspot capacity, and massive connections with high reliability, low latency with reduced power consumption.

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• COMPUFOX SFP+ Direct Attach Copper Cables Solution

  Feb 27, 2016 by Articles / 595 Views

  Overview
  SFP+ Direct Attach Copper Cable, also known as Twinax Cable, is an SFP+ cable assembly used in rack connections between servers and switches. It consists of a high speed copper cable and two SFP+ copper modules. The SFP+ copper modules allow hardware manufactures to achieve high port density, configurability and utilization at a very low cost and reduced power budget.

  Direct Attach Cable assemblies are a high speed, cost-effective alternative to fiber optic cables in 10Gb Ethernet, 8Gb Fibre Channel and InfiniBand applications. They are suitable for short distances, making them ideal for highly cost-effective networking connectivity within a rack and between adjacent racks. They enable hardware OEMs and data center operators to achieve high port density and configurability at a low cost and reduced power requirement.

  Compufox SFP+ copper cable assemblies meet the industry MSA for signal integrity performance. The cables are hot-removable and hot-insertable: You can remove and replace them without powering off the switch or disrupting switch functions. A cable comprises a low-voltage cable assembly that connects directly into two SFP+ ports, one at each end of the cable. The cables use high-performance integrated duplex serial data links for bidirectional communication and are designed for data rates of up to 10 Gbps.

  Types of SFP+ Direct Attach Copper Cables

  SFP+ Direct Attach Copper Cable assemblies generally have two types which are Passive and Active versions.
  
  

  SFP+ Passive Copper Cable
  SFP+ passive copper cable assemblies offer high-speed connectivity between active equipment with SFP+ ports. The passive assemblies are compatible with hubs, switches, routers, servers, and network interface cards (NICs) from leading electronics manufacturers like Cisco, Juniper, etc.

   

  SFP+ Active Copper Cable
  SFP+ active copper cable assemblies contain low power circuitry in the connector to boost the signal and are driven from the port without additional power requirements. The active version provides a low cost alternative to optical transceivers, and are generally used for end of row or middle of row data center architectures for interconnect distances of up to 15 meters.

   

  Applications of SFP+ Direct Attach Copper Cables

  -Networking – servers, routers and hubs

  -Enterprise storage

  -Telecommunication equipment

  -Network Interface Cards (NICs)

  -10Gb Ethernet and Gigabit Ethernet (IEEE802.3ae)

  -Fibre Channel over Ethernet: 1, 2, 4 and 8G

  -InfiniBand standard SDR (2.5Gbps), DDR (5Gbps), and QDR (10Gbps)

  -Serial data transmission

  -High capacity I/O in Storage Area Networks, Network Attached Storage, and Storage Servers

  -Switched fabric I/O such as ultra high bandwidth switches and routers

  -Data center cabling infrastructure

  -High density connections between networking equipment

   

  Compufox SFP+ Direct Attach Copper Cables Solution

  Compufox SFP+ twinax copper cables are avaliable with custom version and brand compatible version. All of them are 100% compatible with major brands like Cisco, HP, Juniper, Enterasys, Extreme, H3C and so on. If you want to order high quality compatible SFP+ cables and get worldwide delivery, we are your best choice.

  For instance, our compatible Cisco SFP+ Copper Twinax direct-attach cables are suitable for very short distances and offer a cost-effective way to connect within racks and across adjacent racks. We can provide both passive Twinax cables in lengths of 1, 3 and 5 meters, and active Twinax cables in lengths of 7 and 10 meters. (Tips: The lengths can be customized up to the customers' requirements.)

  Features
  -1m/3m/5m/7m/10m/12m available

  -RoHS Compatible

  -Enhanced EMI suppression

  -Low power consumption

  -Compatible to SFP+ MSA

  -Hot-pluggable SFP 20PIN footprint

  -Parallel pair cable

  -24AWG through 30AWG cable available

  -Data rates backward compatible to 1Gbps

  -Support serial multi-gigabit data rates up to 10Gbps

  -Support for 1x, 2x, 4x and 8x Fibre Channel data rates

  -Low cost alternative to fiber optic cable assemblies

  -Pull-to-release retractable pin latch

  -I/O Connector designed for high speed differential signal applications

  -Temperature Range: 0-70°C

  -Passive and Active assemblies available (Active Version: Low Power Consumption: < 0.5W Power Supply: +3.3V)

   

  FAQ of Compufox SFP+ Direct Attach Copper Cables

  Q: What are the performance requirements for the cable assembly?
  A: Our SFP+ copper passive and active cable assemblies meet the signal integrity requirements defined by the industry MSA SFF-8431. We can custom engineer cable assemblies to meet the requirements of a customer’s specific system architecture.

  Q: Are passive or active cable assemblies required?
  A: Passive cables have no signal amplification in the assembly and rely on host system Electronic Dispersion Compensation (EDC) for signal amplification/equalization. Active cable assemblies have signal amplification and equalization built into the assembly. Active cable assemblies are typically used in host systems that do not employ EDC. This solution can be a cost savings to the customer.

  Q: What wire gauge is required?
  A: We offer SFP+ cable assemblies in wire gauges to support customers' specific cable routing requirements. Smaller wire gauges results in reduced weight, improved airflow and a more flexible cable for ease of routing.

  Q: What cable lengths are required?
  A: Cable length and wire gauge are related to the performance characteristics of the cable assembly. Longer cable lengths require heavier wire gauge, while shorter cable lengths can utilize a smaller gauge cable.

  For all you SFP+ Direct attach cables, please see link below. We carry compatible cables for most major brands.

  http://www.compufox.com/SFP_Cables_s/337.htm

      

  

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• Standards and Recommendations for Fiber Optic Systems

  Feb 5, 2016 by Articles / 577 Views

  Many international and national standards govern optical cable characteristics and measurement methods. Some are listed below, but the list is not exhaustive. Releases are subject to change.

  International Standards

  Two main groups are working on international standards: International Electrotechnical Commission (IEC) and International Telecommunication Union (ITU).

  IEC: The IEC is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies, which serve as a basis for national standardization.

  The IEC is composed of technical committees who prepare technical documents on specific subjects within the scope of an application in order to define the related standards. For example, the technical committee TC86 is dedicated to fiber optics, and its subcommittees SC86A, SC86B, and SC86C focus on specific subjects such as: SC86A: Fibers and CablesSC86B: Fiber Optic Interconnecting Devices and Passive ComponentsSC86C: Fiber Optic Systems and Active Devices

  ITU: The ITU is an international organization that defines guidelines, technical characteristics, and specifications of telecommunications systems, networks, and services. It includes optical fiber performance and test and measurement applications and consists of three different sectors: Radiocommunication Sector (ITU-R)Telecommunication Standardization Sector (ITU-T)Telecommunication Development Sector (ITU-D)

   

  National Standards

  In addition to the international standards, countries or union of countries define their own standards in order to customize or fine tune the requirements to the specificity of their country.

  European Telecommunications Standards Institute

  The European Telecommunications Standards Institute (ETSI) defines telecommunications standards and is responsible for the standardization of Information and Communication Technologies (ICT) within Europe. These technologies include telecommunications, broadcasting, and their related technologies, such as intelligent transportation and medical electronics.

  Telecommunication Industries Association / Electronic Industries Alliance

  The Telecommunication Industries Association (TIA) provides additional recommendations for the United States. TIA is accredited by the American National Standards Institute (ANSI) to develop industry standards for a wide variety of telecommunications products. The committees and subcommittees define standards for fiber optics, user premises equipment, network equipment, wireless communications, and satellite communications.

  NOTE: There are many other standard organizations that exist in other countries.

   

  Fiber Optic Standards

  By IEC: IEC 61300-3-35: Fibre Optic Connector End Face Visual InspectionIEC 60793-1 and -2: Optical Fibers (includes several parts)IEC 60794-1, -2, and -3: Optical Fiber Cables

  By ITU: G.651: Characteristics of 50/125 μm Multimode Graded-index Optical FiberG.652: Characteristics of Single-mode Optical Fiber and CableG.653: Characteristics of Single-mode Dispersion Shifted Optical Fiber and CableG.654: Characteristics of Cut-off Shifted Single-mode Optical Fiber and CableG.655: Characteristics of Non-zero Dispersion Shifted Single-mode Optical Fiber and CableG.656: Characteristics of Non-zero Dispersion Shifted Fiber for Wideband TransportG.657: Characteristics of a Bending Loss Insensitive Single-mode Fiber for Access Networks

   

  Test and Measurement Standards

  Generic Test Standards: IEC 61350: Power Meter CalibrationIEC 61746: OTDR CalibrationG.650.1: Definition and Test Methods for Linear, Deterministic Attributes of Single-mode Fiber and CableG.650.2: Definition and Test Methods for Statistical and Non-linear Attributes of Single-mode Fiber and Cable

  PMD Test Standards: G.650.2: Definition and Test Methods for Statistical and Non- linear Attributes of Single-mode Fiber and CableIEC 60793 1-48: Optical Fibers—Part 1-48: Measurement Methods and Test Procedures—Polarization Mode DispersionIEC/TS 61941: Technical Specifications for Polarization Mode Dispersion Measurement Techniques for Single-mode Optical FiberIEC 61280-3/TIA/TR-1029: Calculation of PolarizationTIA 455 FOTP-124A: Polarization Mode Dispersion Measurement for Single-mode Optical Fiber and Cable Assemblies by InterferometryTIA 455 FOTP-113: Polarization Mode Dispersion Measurement of Single-mode Optical Fiber by the Fixed Analyzer MethodTIA 455 FOTP-122A: Polarization Mode Dispersion Measurement for Single-mode Optical Fiber by the Stokes Parameter MethodTIA TSB-107: Guidelines for the Statistical Specification of Polarization Mode Dispersion on Optical Fiber CablesTIA 455-196: Guidelines for Polarization Mode Measurements in Single-mode Fiber Optic Components and DevicesGR-2947-CORE: Generic Requirements for Portable Polarization Mode Dispersion (PMD) Test SetsIEC 61280-4-4: Polarization Mode Dispersion Measurement for Installed LinksTIA 445 FOTP-243: Polarization Mode Dispersion Measurement for Installed Single-mode Optical Fibers by Wavelength-scanning OTDR and State of Polarization Analysis

  CD Test Standards: G.650.1: Definition and Test Methods for Linear, Deterministic Attributes of Single-mode Fiber and CableIEC 60793 1-42: Optical Fibers—Part 1-42: Measurement Methods and Test Procedures—Chromatic DispersionIEC 61744: Calibration of Fiber Optic Chromatic Dispersion Test SetsTIA/EIA FOTP-175-B: Chromatic Dispersion Measurement of Single-mode Optical FibersGR-761-CORE: Generic Criteria for Chromatic Dispersion Test SetsGR-2854-CORE: Generic Requirements for Fiber Optic Dispersion Compensators

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