WiFi World Summit: Seamless WiFi Is Coming
Three wireless technology events came together in Barcelona. The goal: develop a network where your phone will automatically switch to WiFi when you're indoors.…
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Measure throughput of cellular and WiFi MIMO radios
As cellular and Wifi systems move from single to multiple wireless signals, handsets and the chipsets that go inside them need testing. Because of the multiple signals in a MIMO (multiple input, multiple output) system, testing handsets using a wired connection doesn’t emulate the needed test conditions.
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May –June 2014
Test MIMO Wi-Fi and LTE radios over the air
Radio technologies such as IEEE 802.11 and 3GPP (3rd generation partnership project) LTE rely on MIMO (multiple input, multiple output) techniques to increase the range and data rates of radio transmissions. Using digital-signal processing, MIMO radios sense the conditions in the channel on a packet-by-packet basis and make instantaneous decisions on whether to employ 802.11 or LTE techniques.
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Testing modern MIMO Wi-Fi and LTE radios
MODERN RADIO TECHNOLOGIES such as the IEEE 802.11 and 3GPP (3rd generation partnership project) LTE (long term evolution) rely on MIMO (multiple input multiple output) techniques to increase the radio transmission range and speed. MIMO algorithms use multiple synchronized radios (up to 4 for 802.11n and LTE; up to 8 for the emerging 802;11ac) to adapt to continuously changing conditions in the wireless channel.
Multimode vector radio dismantles barriers to SDR software portability
In the age of diverse and unsettled wireless standards, the market needs flexible multiprotocol radios for handsets and basestations. These radios must be instantly self-configurable to roam from traditional GSM and CDMA networks to the expanding UMTS and LTE areas of coverage.
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Multimode wireless devices: It’s the software, stupid!
Since the dawn of cellular communications in the mid-seventies, the industry has advanced through three generations of radio standards and is about to launch 4G. New wireless technologies continue to emerge while the old ones linger, forcing wireless equipment, both phones and base stations, to support multiple radio interfaces where interoperability is required.
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Rethinking portable power specs for 'YouTube minutes'
Handset manufacturers have yet to specify "projector minutes" or "YouTube minutes." But yesterday's "talk time" and "standby time" specs are inadequate for today's multimedia world, and the industry knows it. The truth is, our 10-year-old lithium-ion battery technology can only provide a few hours of life to modern applications. Manufacturers and carriers are trying to hide this inadequate performance behind obscure specifications based on usage profiles.
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Sharing TV spectrum may require cognitive radio technology
In the early days of broadcast TV, the world was analog and spectrum was plentiful. Spectrum sharing was unnecessary and, indeed, hadn't even been invented. Dedicated spectrum was allocated to each TV channel and later, 202 wireless microphones were permitted to operate in unused channels (FCC part 74). view article .pdf
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Wireless HD video: Raising the UWB throughput bar (again)
This article reviews the promise and technical challenges facing UWB, reports on the most recent test results, and analyzes a particular approach to UWB. It also discusses the throughput and encryption considerations for HD video distribution. view article .pdf
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 article .pdf
Will 802.11n be a good neighbor?
On June 25, the Wi-Fi Alliance (www.wi-fi.org
) officially started its 802.11n draft 2.0 certification, and products from 14 vendors (and counting) are now certified. But will these new products work well side-by-side with their legacy counterparts? Can they be phased into the existing network gradually, or will 802.11n systems require exclusively 802.11n equipment? view article .pdf
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Report: Tests show 802.11n outperforming 802.11g
Wireless LAN systems based on draft-compliant IEEE 802.11n chipsets from four vendors are significantly outperforming 802.11g-based systems—although with notable variations between products. Since the Wi-Fi Alliance began certifying draft 802.11n products on June 25, the number of certified devices has been growing steadily and is now over 50. The Wi-Fi Alliance expects these products to interoperate and to deliver approximately twice the range and five times the throughput of legacy 802.11a/b/g networks. view .pdf
Taming the Beast: 802.11n Coexistence with legacy networks
Since testing began on June 25 2007, the Wi-Fi Alliance has been certifying 802.11n draft 2.0 devices for interoperability and backwards compatibility. As of this writing, the number of certified products is 14 and counting. Will these devices disrupt legacy networks? Will 802.11n-based video streaming applications operating in the double-width 40 MHz channels squeeze out low data rate applications such as VoIP and remote control? view article .pdf
Given the complex behavior of MIMO/OFDM signals interacting with the environment, some form of channel emulation is essential in providing an adequate picture of performance. view article .pdf
Wireless LAN (WLAN) throughput advancements introduced by the emerging IEEE 802.11n standard come at the price of unprecedented technological complexity. This creates an immediate need for sophisticated test systems that can help manufacturers and service providers bring robust, well tested products to market. Although the final standard will not be published until mid-2009, draft 2.0 is now mature enough that companies such as Intel, Broadcom, Atheros, Marvell, and Qualcomm have already released 802.11n chipsets that will require only software changes in order to comply with the final standard. view article .pdf
802.11n: The next generation in Wireless LAN technology
MIMO is the key for high-throughput wireless networking. view article .pdf
The challenges and importance of testing mesh networks prior to deployment
Despite the rapid growth of wireless mesh networking technology as the primary infrastructure for several broadband services, including wide-area voice and data transmission, the industry lacks an established process for testing wireless mesh networks. And, without thorough testing, mesh networks cannot be deployed on a large scale. Consequently, pre-deployment testing that automates the performance testing of wireless mesh networks in a controlled laboratory environment is required to establish its credibility for mission-critical metro-area network applications. view article .pdf
How will 802.11T help test Wi-Fi?
Buyers of Wi-Fi equipment and systems must be assured that all products have the performance and stability to carry mission-critical applications and data. However, testing of Wi-Fi, or 802.11, devices and systems for performance and stability is a challenge for the industry because of the complexity of the 802.11 protocol. That is compounded by the inherent mobility of the wireless devices and the prevalence of radio frequency interference. view article .pdf
802.11T puts WLANs to the test
Buyers of Wi-Fi equipment and systems must be assured that all products have the performance and stability to carry mission-critical applications and data. However, testing of Wi-Fi, or 802.11, devices and systems for performance and stability is a challenge for the industry because of the complexity of the 802.11 protocol. That is compounded by the inherent mobility of the wireless devices and the prevalence of radio frequency interference. view article URL
March 16, 2006
New standard to bring broadband video over WiFi to conferencing market
Simple connectivity has helped make IEEE 802.11-based Wi-Fi the network technology of choice where data cabling is scarce. No longer tethered to a desk, you can browse the Net or collaborate with colleagues from anywhere there is a Wi-Fi signal. Could the next step in corporate conferencing be broadband video over Wi-Fi?view article URL
February 27, 2006
Cellular or WiFi
As the adage goes: “The good thing about standards is that there are so many of them.” Does the world need yet another one? Yes—to converge a few of the existing ones. Convergence of WiFi and cell technologies in a single handset will enable pervasive access to voice and data indoors and out with one standard, one network, and one device. view article URL
April 1, 2005
Metrics And Methods Bring VoWLAN Success
Mobile phones have been a runaway success for two decades. Over the years, however, the cellular market has stabilized. Can Wi-Fi give the cell-phone industry a boost? The IEEE 802.11- based Wi-Fi data-networking technology has penetrated the small-office/home-office (SOHO) market. Now, it is expanding rapidly into the enterprise and public-access markets. Wi-Fi is well suited to carry packetized voice, such as Voice over IP. It also can offer cellular users better indoor coverage at a lower cost
WiFi Testing Using a Cabled RF Environment
As Wi-Fi technology matures, wireless LANs are moving from the relatively tolerant SOHO market to the demanding enterprise — a market where high network performance is needed to support mission-critical applications, a large number of network users, and a diversity of network elements. Enterprise IT managers need accurate performance data on wireless systems to ensure the interoperability, functionality, and performance of the wireless infrastructure. Testing of wireless access points, clients, and networks is critical to developing WLANs hardy enough for enterprise adoption. Yet WLAN testing is often conducted in unstable environments where it is impossible to ensure the repeatability and reliability of test outcomes. The result is a testing process that is costly and unreliable. view article URL
The IEEE 802.11 Wireless Local Area Network (WLAN) technology, commonly known as Wi-Fi, has been steadily gaining popularity, keeping users on the go productively connected at airports, in hotels, and even in front of living room TV sets. Most of us who have experienced the freedom and flexibility of wireless connectivity have no wish to return to tethered networking. So far, wireless networking has been largely confined to the airport, hotel, coffee-shop, and small-office home-office (SOHO) markets, where performance is less important than cost. The new target for the wireless industry is the lucrative enterprise market, but those of us who yearn for 802.11 to take hold in the enterprise have to wait until the technology proves itself sufficiently robust and ready to carry demanding mission-critical applications. In enterprises, network performance impacts productivity, and IT executives won’t make the decision to deploy 802.11 lightly.
October 1, 2004
Broadband 101: Installation and Testing
Today the Internet is an information superhighway with bottlenecks at every exit. These congested exits call for the deployment of broadband access to the homes and businesses. Broadband technology lets you watch TV (video), browse the Internet via a high-speed connection (data) and use the phone (voice) simultaneously. Broadband access means support for data, voice and video services over a single cable with an “always-on” connection. view article .pdf
Fiber Optic Gigabit Transmission and 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. view article .pdf