Wireless personal testbeds



Download the whitepaper
MU-MIMO – a practical example
Servicing a large number of clients that are using small packets with legacy Wi-Fi is inefficient because the overheads incurred by the preamble and other mechanisms tend to dominate. OFDMA is ideally suited for this scenario because it divides up the channel and services up to 37 users simultaneously, which amortizes the overhead. OFDMA improves system efficiency, but it does not necessarily improve throughput.
MU-MIMO creates spatially distinct separate channels between the transmitter and each of a small number of receivers such that each receiver hears only the information intended for itself, and not the information intended for other receivers. download this whitepaper

Download the whitepaper
Triathlon: RF, MAC, PHY analyzer for Wi-Fi 6 (11ax) and legacy Wi-Fi
“Triathlon is a combination of hardware and software that finally makes it possible to analyze wireless data across the RF, PHY and MAC layers, and provides the ability to correlate information among the layers and to drill down easily to any issue being explored. Packet sniffers make it possible to look at protocol elements across various layers of the OSI protocol stack. However, the realms of “RF analysis” and “protocol analysis” have long been completely separate, leading to wasted time and energy as teams with different tools attempt to jointly debug solutions Triathlon merges those two domains together, making it possible for teams with expertise in those various domains to analyze data together, and to solve problems faster.” download this whitepaper

Download the whitepaper
Small Anechoic Chamber Channels: Estimating Channel Capacity from a Chamber Model
“MIMO systems are dependent on the spatial orientation of the antennas at both ends of the links and the geometry of the antenna arrays themselves. The development and deployment of next generation devices greatly depends on the ability to test and analyze the devices under realistic conditions; it is for this purpose that MIMO-OTA testing platforms are being developed.” get this whitepaper (registration required)

Download the whitepaper
Near-Field MIMO Channel Modeling with Applications to Small Anechoic Chambers
“there is a lack of knowledge of MIMO in the near field. Near-field (specifically Fresnel region and near the Fraunhofer distance) MIMO channels define the performance of these systems, therefore a robust method of near-field MIMO channel modeling is needed to aid in system design and testing. … ” get this Ph. D. dissertation (registration required)

Download the whitepaper
Repeatable and Reproducible Measurements Using the octoBox Personal Testbed
Wireless testing should be both repeatable and reproducible, and the octoBox personal testbed delivers on both goals. Although the two concepts are different, the words are sometimes used interchangeably. For the sake of clarity, we will provide our definitions of them here. … get this whitepaper (registration required)

Download the whitepaper
802.11 MCS and Data Rate Calculator
An Excel spreadsheet with a few adjustable variables: Enter the conditions and find the minimum expected MCS and data rate. get this Excel spreadsheet (registration required)

Download the whitepaper
Path Loss vs Distance
An Excel spreadsheet with a few adjustable variables. get this Excel spreadsheet (registration required)

Download the Article
Throughput Test Methods For Mimo Radios: Achieving high throughput and repeatable results
This paper discusses the challenges and methods of achieving maximum MIMO throughput and repeatable measurements over a wide dynamic range and under a variety of wireless channel conditions. It focuses on MIMO over the air (OTA) test methods. get this whitepaper (registration required)

Download the Article
HOW DO MIMO RADIOS WORK? - Adaptability of Modern 802.11 and LTE Technology
New generation Multiple Input Multiple Output (MIMO) 802.11n/ac radios have more complex adaptation algorithms than legacy Single Input Single Output (SISO) 802.11a/b/g devices. While SISO devices only vary modulation, 802.11n/ac radios work with a more complex Modulation Coding Scheme (MCS). An MCS includes the following variables: modulation, coding rate, GI, channel width and the number of spatial streams.… download this whitepaper

Download the whitepaper
MIMO Data Rate Computation
A concise useful summary: Spreadsheet providing 802.11n/ac data rate computation for each standard Modulation Coding Scheme (MCS) get this whitepaper (registration required)

Download the Article
Wireless Technology Assessment for Automotive Applications
Recently, automotive safety applications with wireless communications have been the focus of worldwide research and development. DSRC (Dedicated Short Range Communications) in particular, with its low latency vehicle-to-vehicle connectivity, now appears to be a promising wireless technology for time-sensitive crash avoidance applications. download this whitepaper

Download the Article
IEEE 802 Wireless Summary – Amendments under Development
Three (3) pages of status updates. download this whitepaper

Download the Article
Wireless Technology Assessment for Automotive Application
In this paper, we first examine major automotive applications, including emerging applications, and then discuss wireless technologies and standards best suited to support these applications. download this whitepaper

Download the Article
MIMO/OTA Test Methodology Consideration for Small Anechoic Chambers
Single-cluster MIMO/OTA measurements can be accommodated by small anechoic chambers that are modestly priced and have minimal space requirements. This contribution explores geometry requirements pertinent to single cluster measurements per TR 37.976. download this whitepaper

Download the Article
IEEE 802 Wireless Summary – Amendments under Development
A concise, useful summary. get this whitepaper (registration required)

Download the Article
Software-based MIMO Channel Emulator
Fox is a software based channel emulator that models a wireless channel with up to 4x4 MIMO paths. While currently supporting 802.11n channel models, Fox can be extended to incorporate other channel models, including LTE and a variety of military or proprietary models. Fox works on MIMO streams of IQ samples and operates in the National Instruments LabVIEW application development and graphical programming environment. Fox takes as input a sampled 802.11n baseband signal stored in a file, mathematically applies 802.11n channel models and other distortion to this signal and outputs the resulting signal to a file. view whitepaper .pdf

Download the Article
Open Spectrum: New Standards Big Prospects
At the turn of the 20th century spectrum was, much like the Wild West, unregulated and free, but things have changed. Dramatic advances in wireless technology have spurned elaborate regulations from the FCC and its international counterparts. But spectrum regulations have traditionally lagged the evolving needs of the wireless world. TV broadcasting, the dominant wireless technology of its time, gave way to cellular and wireless broadband communications. And now the FCC regulations designed for the broadcasting age must evolve to meet the needs of mobile users. view whitepaper URL

UWB Test Report
Comprehensive UWB tests give video a green light but caution on wireless USB
With 22 UWB based Wireless-USB products being certified, it’s time to evaluate UWB technology. While most WiMedia Alliance entries ran at less than 10% of the 480 Mbits/s PHY rate over short distances, Pulse-LINK’s CWave technology was fast enough for multiple HD video streams over good distances. view whitepaper .pdf

802.11n draft 2.0
Wi-Fi CERTIFIED™ 802.11n draft 2.0: Longer-Range, Faster-Throughput, Multimedia-Grade Wi-Fi® Networks
Wi-Fi CERTIFIED 802.11n draft 2.0 is a certification program for products based upon the IEEE draft 2.0 802.11n specification. At this writing, the final 802.11n amendment to the IEEE 802.11 standard is expected to be released in the second half of 2008. 802.11n is a major next step in the evolution of WLAN technology and represents more than just a new physical layer.

Download the Article
Test Strategies for 802.11n MIMO Devices
True to the trend of ever-increasing data rates, the new IEEE 802.11n WLAN (Wireless LAN) transmission technology based on MIMO (Multiple Inputs/Multiple Outputs) guarantees throughput of at least 100 Mbps but can deliver up to 600 Mbps depending on the complexity of the 802.11n radio and on the environment. MIMO is a highly innovative advancement in wireless data transmission. It turns the long-time nemesis of wireless – multipath – into a friend. Multipath is a common occurrence indoors where the wireless signal reflects from surfaces thus creating multiple signals that add together in the air. While today’s 802.11 a/b/g radios struggle to separate the original signal from this muddle, the MIMO radio actually takes advantage of multipath to send multiple data streams via the available paths. get this whitepaper (registration required)

Download the Article
IEEE802.11T – WLAN Test Methods and Metrics
Until now the surge of wireless networking has been largely confined to the SOHO market, where performance has taken a second place to cost. The new applications for the WLAN industry are voice and video services that depend on performance. Formally defining performance test methods and metrics is a timely and important undertaking. Proper testing will shine the light on performance issues and will help the WLAN industry to expand into the emerging cellular and streaming video markets. download this whitepaper

Download the Article
Quality Metrics for Network Services
Year after year enterprises make significant investments to improve the quality of network services either through faster equipment or through more efficient protocols. Yet, the networking industry still does not have any objective metrics for Quality of Service (QoS). Different industry sectors have their own definitions of quality. QoS is defined in three different unrelated ways at the Ethernet layer, at the IP layer and for the ATM networks. These disparate definitions of quality confuse the market and offer no objective metrics of acceptable quality. download this whitepaper

Download the Article
Level III Tester Accuracy
Field testers certifying category 6 installations must conform to the Level III accuracy specifications defined by TIA and ISO. When you invest time and money into the certification job you want to be sure that the certification work is valid. The best way to ensure certification validity is to use a tester that is independently verified to meet Level III. The Agilent WireScope 350 has been independently verified by ETL to meet all Level III requirements in both the Permanent Link and Channel configurations. This white paper explains what Level III accuracy is and shows the independent verification test results for the WireScope 350. download this whitepaper

Download the Article
The Monster Cords
Does our industry need bulky and expensive Permanent Link test cords and complex field calibration procedures to support Category 6 testing? Does a monster cord provide better measurement repeatability or longer life? This paper demonstrates that the answer to both questions is no. download this whitepaper

Download the Article
Fiber Optic Test Issues – What to Measure and Why?
Fiber optic networking applications, such as Gigabit Ethernet, the emerging 10 Gigabit Ethernet and Storage Area Networks (SANs) are focusing much of the industry’s attention on the need to properly evaluate fiber optic installations. Today there is no simple standards-based test method to assure that the installed cabling can support new fiber optic applications. download this whitepaper

Download the Article
Understanding FEXT and ELFEXT
Far end crosstalk is a source of noise for twisted pair networks that use more than one pair for transmission. It is important to qualify far end crosstalk on the cabling used for running gigabit Ethernet. download this whitepaper

Download the Article
Category 6 – The Ultimate Challenge
Life was easy back in the category 5 days, although many of us did not think so back then. Today, faced with the challenges of category 6, all of us can appreciate the good old days. Why is certifying category 6 so much harder than certifying category 5? The simple answer is – the test limits got significantly stricter but the cabling technology is still catching up to these limits. The result? High failure rate on category 6 installations. download this whitepaper

Download the Article
10 Gigabit Ethernet Field Testing Issues
Today’s fiber optic installations are fast increasing in number and in bandwidth to alleviate the throughput bottlenecks on the backbone networks where traffic from multiple workstations aggregates. This article examines the latest developments in high speed Ethernet transmission over fiber optic media and discusses the new field testing issues associated with these emerging standards. download this whitepaper

Download the Article
Gigabit Transmission − What’s the Limit?
As Local Area Networking (LAN) technology advances into the realm of gigabit transmission, cabling infrastructure is evolving to address the new physical layer requirements of the new networks. This paper examines the signaling environment pertaining to the new generation gigabit transmission over twisted pair and fiber optic cabling and discusses methods of measuring the headroom of network applications in the field. download this whitepaper

Download the Article
Cable Analysis-Extracting Information from Measured Data
Every cable tells a story. Cable certification measurements can be presented as a string of numbers or as a series of plots. Most of us are not good at reading numbers. It is much easier to interpret graphical information. This paper explains how to extract information from certification plots and talks about the importance of preserving plot data for future analysis. download this whitepaper

Download the Article
Understanding the Dynamic Range Requirements for Far End Crosstalk Measurements
This paper examines the requirements for instrument dynamic range when performing field certification of ELFEXT per TSB95, "Additional Transmission Performance Guidelines for 100 Ω 4-Pair Category 5 Cabling " and TIA-568-A-A5, "Additional Transmission Performance Specifications for 4-Pair 100 Ω Enhanced Category 5 Cabling". download this whitepaper

Download the Article
Gigabit Ethernet Over Category 5
The twisted pair gigabit Ethernet standard – 1000Base-T – is under development by the IEEE P802.3ab task force and is expected to be ratified in the first half of 1999. The work on this standard started in the latter half of 1996. In September 1997, after a year of debate, the IEEE P802.3ab task force selected the Enhanced TX/T2 line code for implementing 1000Base-T. The name – Enhanced TX/T2 – was chosen because this signaling scheme has inherited the symbol rate and spectrum of 100Base-TX and is based on the line code used by 100Base-T21. view article .pdf

Download the Article
The Inter-standard Gap
In an ideal world the networking and the cabling standards would be inter-operable. The IEEE, ANSI and The ATM-Forum standards committees developing new networking standards could simply specify a cable plant compliant with TIA-568-A[1] or ISO11801[2]. This kind of cooperative arrangement among the standards organizations could eliminate the redundancy of standardization effort and the duplication of work. But when dealing with the enormous complexity of data communications, can we honestly believe that a jump from 10 to 100 Mb/s will happen flawlessly and quickly, just as the standards dictate? Has any significant advancement in networking technology ever occurred without inter-operability issues? This paper provides an overview of the emerging 100 Mb/s Local Area Networking (LAN) applications − their physical layer needs and specifications. It examines how well the generic cabling standards such as TIA-568-A[1] and ISO11801[2] address the requirements of the emerging high speed LANs and demonstrates some gaps between the ideal world and the reality today. How close are we to our goal of standards interoperability? Can the industry standards ever catch up with the accelerating pace of advancements in the data communications industry? Before we attempt to answer these questions, let’s examine the facts. view article .pdf

Download the Article
The ATM Controversy
The question of whether the 155 Mb/s ATM interface is properly supported by category 5 cabling has been a topic of some disagreement. Unfortunately for the end user of ATM, the importance of the channel bandwidth above 100 MHz has, on occasion, been misrepresented so as to promote systems and test equipment unspecified above 100 MHz. Category 5, as specified, does not satisfy the requirements of the 155 Mb/s ATM network This fact is supported by theoretical analysis and by experiment1. However, in the interest of allowing the existing standards to become established, the physical layer requirements of this network have sometimes been presented from the “best case” perspective. This paper analyzes the channel bandwidth requirements of a few widely used 155 Mb/s ATM products in the context of the best and worst case conditions defined by the ATM Forum AF-PHY-0015.000 and TIA- 568 standards and demonstrates that typical ATM products rely on the channel bandwidth beyond 100 MHz for proper operation. download this whitepaper

Download the Article
Analysis of Physical Layer Requirements for 155 Mb/s Twisted Pair ATM
This paper analyzes the physical layer operation of 155 Mb/s twisted pair ATM equipment, presenting a detailed examination of channel bandwidth utilization and the performance trade-offs inherent in various bandwidth limiting techniques. The data and analysis developed here support the conclusion that in order to meet the required Bit Error Rate of 10-10, the 155 Mb/s ATM application relies on the channel frequency response beyond the 100 MHz band specified by category 5. download this whitepaper