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- 802.11n: MIMO really needs smart antennas
- As Wi-Fi standards go, 802.11n has a lot to live up to, especially after hearing how 802.11n's advertised throughput, security, and reliability will allow Wi-Fi to replace existing wired networks. This means 802.11n's RF technology needs to be rock-solid, just like Ethernet cables, while facing ever-changing environmental conditions. ...
- Tags: Device, Network, Signal, IEEE 802.11n, Interference, MIMO, Technology, Antenna, RF, Ruckus Wireless, Antenna Diversity, N, Beamforming, BeamFlex, Path Control Module, Ruckus, Wi-Fi, Wireless LANs, Wireless, Michael Kassner
- Blog posts 2008-05-14
Additional Resources
- A Low Complexity Antenna Diversity Receiver for OFDM Based Systems
- A low complexity antenna diversity architecture with a new combining technique suitable for Orthogonal Frequency Division OFDM based systems is introduced in this paper. For a two branch antenna diversity, this structure requires only one FFT at the receiver and allows optimum maximum ratio combining. For systems with a higher...
- Tags: Technique, OFDM, Productivity, Wireless
- White papers
- Capacity Scaling of Ad Hoc Networks With Spatial Diversity
- This paper derives the exact outage probability and transmission capacity of ad hoc wireless networks with nodes employing multiple antenna diversity techniques. The analysis enables a direct comparison of the number of simultaneous transmissions achieving a certain data rate under different diversity techniques. Preliminary results derive the outage probability and...
- Tags: Advertisement, University Of Texas, Productivity, Wi-Fi, Wireless
- White papers 2007-01-23
- How to make the best of 802.11 multipath environments
- In a post titled Wi-Fi 101: Multipath environments and how they affect Wi-Fi propagation, I examined what happens to 802.11 RF signals when they encounter physical obstacles. I would like to take the next logical step and develop quantifiable relationships between three different Line of Sight LoS environments and the...
- Tags: IEEE 802.11, Environment, Technology, Antenna, RF, Free Space Path Loss, Multipath Interference, Diversity Scheme, Receiver, Wireless LANs, Wi-Fi, Wireless, Michael Kassner
- Blog posts 2007-10-30
- iMAT: MIMO without multiple antennas
- Antenna systems are not normally a preeminent topic when it comes to discussions about wireless equipment. That attitude is completely understandable; antennas are just not that interesting to most people. To some, including myself, RF propagation and antenna technology are very worthy discussion topics. My fascination started 40 years ago...
- Tags: Situation, MIMO, Antenna, iMAT, Antenna System, RF, EM, EM Isolation, SkyCross, iMAT Antenna System, Michael Kassner
- Blog posts 2008-02-25
- 802.11n, MIMO, and multipath environments
- In two previous posts-Multipath environments and how they affect Wi-Fi propagation and How to make the best of 802.11 multipath environments-I examined the somewhat nebulous topic of multipath fading and technologies that minimize the negative effects on Wi-Fi networks. Now I'm going to pull a 180 and talk about how...
- Tags: Environment, IEEE 802.11n, MIMO, Multipath, SISO, Michael Kassner
- Blog posts 2007-11-12
- Diversity Reception for OFDM Systems Using Antenna Arrays
- Orthogonal Frequency Division Multiplexing OFDM is a multicarrier modulation scheme that achieves high spectral efficiency by using minimally densely spaced orthogonal subcarriers without increasing the transmitter and receiver complexities. Antenna arrays are a powerful means to exploit the spatial domain to provide an extra layer of co-channel interference cancellation and...
- Tags: IEEE, Antenna Array, Array-OFDM System, OFDM, Wireless
- White papers 2005-12-01
- On Cyclic Delay Diversity in OFDM Based Transmission Schemes
- Cyclic Delay Diversity CDD is a simple approach to introduce spatial diversity to an Orthogonal Frequency Division Multiplexing OFDM based transmission scheme that itself has no built-in diversity. It also can be regarded as a Space-Time Code STC. But in contrast to that there is no additional effort in the...
- Tags: Diversity, University Of Ulm, Cyclic Delay Diversity, OFDM, Wireless
- White papers
- Cooperative Diversity in Wireless Networks: A Geometry-Inclusive Analysis
- Cooperation between physically separated wireless nodes can achieve the high Signal-to-Noise Ratio SNR diversity gains characteristic of multi-antenna arrays. Simulations indicate that such gains are still achieved for SNRs in the range of practical interest for several applications. Cooperation further yields SNR gains in addition to diversity gains. In contrast...
- Tags: Network, Gain, Wireless Network, SNR, Wi-Fi, Wireless
- White papers 2006-03-10
- ADAPTIVE Space Diversity for Multicarrier CDMA Schemes Over Fading Radio Channels
- The application of adaptive space diversity combining algorithms in a mobile radio system is presented in this paper. Linear Square Root Kalman and non-linear Recurrent Neural Network based combining algorithms are applied to a Multicarrier Code Division Multiple Access CDMA system for simulation. This novel approach is evaluated over multipath...
- Tags: CDMA, Radio, Multipath, Advertising & Promotion, Marketing
- White papers 2008-04-03
- Downlink Performance and Capacity of Distributed Antenna Systems in a Multicell Environment
- Distributed antenna systems DAS have been widely implemented in state-of-the art cellular communication systems to cover dead spots. Recent academic studies have shown that in addition to coverage improvements, DAS can also allow a capacity improvement. This paper analytically quantifies the performance of downlink multicell DAS in terms of power...
- Tags: Environment, Improvement, University Of Texas, Performance Management, Strategy, Human Resources, Workforce Management, Management
- White papers 2005-04-14
- HSDPA picocell and WiMAX Solutions
- picoChip announced the availability of complete software implementations for HSDPA picocells and 802.16 WiMAX basestations, the PC8218 and PC8520 respectively. The picoChip PC8520 WiMAX basestation solution provides a software-defined implementation of the 802.16-2004 PHY, for the 256OFDM mode with "carrier-class" reliability and performance. The PC8520 enables basestations to be WiMAX-certified....
- Tags: HSDPA, IEEE 802.16, 3G.co.uk, picoChip PC8520, Reference Design Support, WiMAX, Wireless, Wi-Fi
- White papers 2004-09-13
- Blind and Semiblind Spatio-Temporal Diversity for OFDM Systems
- Adaptive antenna arrays can be used to improve the performance of Orthogonal Frequency Division Multiplexing systems. They are usually applied in the frequency domain, after the FFT demodulation. In this paper, the selected algorithms are applied in time domain. A blind method is firstly proposed for the maximization of the...
- Tags: Algorithm, Domain, OFDM, Engineering, Wireless
- White papers
- Configure secure wireless networking on SonicWALL routers
- Wireless networking is a business necessity within most organizations. From traveling employees to guest visitors, wireless networks often prove the best method for connecting these users to e-mail, the Internet and local file shares. Numerous challenges arise when wireless networks are deployed. Besides ensuring a wireless access...
- Tags: Router, Network, SonicWall, WLAN, Wireless Networking, Wizard, Wi-Fi, Wireless, LANs, Networking, Erik Eckel
- Blog posts 2008-04-08
- Perytons Antenna Diversity
- Wireless communications at 2.4 GHz is subject to packet loss due to multi-path interference. This is especially severe in an indoor environment due to reflections from walls and fading due to other objects (e.g. people moving about). Some 2.4 GHz protocols such as Bluetooth use frequency hopping to combat multi-path,...
- Tags: Perytons, Bluetooth, Wi-Fi, Construction, Wireless And Mobility, Networking
- White papers 2008-03-05
- RF interference: Just how important are antennas
- Once again another Good Article.- You just keep them comming, don't you? Well I, for one, am glad of it. While most of that is still above my head, I just don't have enough time, or the the reason, anymore, I still learn from your articles. It's good that's there's...
- Tags: Advertising & Promotion, Adaptive Beamforming
- Discussion threads 2008-06-15
- A Class of Multi-Arm Monopole Antennas for Multi-Band Wireless/Mobile Applications
- This paper presents several multi-band, compact, lightweight and low-cost monopole antennas suitable for applications in the Wireless Local Area Network WLAN and mobile communications. These antennas are two-arm microstrip-fed antenna, two-arm antenna fed by a Co-Planar Waveguide CPW line, three-arm microstrip-fed antenna and a diversity antenna pair composed of two...
- Tags: Mobile, Mobile Application, Antenna, LANs, Wireless, Advertising & Promotion, Wi-Fi, Wireless LANs, Networking, Marketing
- White papers 2005-12-16
- Enterprise 802.11n: The fog may be clearing
- There appears to be some semblance of a master plan rising out of the 802.11n implementation fog. Enterprise equipment developers have done their research and are incorporating additional technologies into 802.11n equipment and by doing so should garner some impressive wireless network performance characteristics. I’d like to point out the...
- Tags: IEEE 802.11n, Guard Interval, Wi-Fi, Wireless, Michael Kassner
- Blog posts 2008-03-19
- Broadband MIMO-OFDM Wireless Communications
- Orthogonal frequency division multiplexing OFDM is a popular method for high data rate wireless transmission. OFDM may be combined with antenna arrays at the transmitter and receiver to increase the diversity gain and/or to enhance the system capacity on time-variant and frequency-selective channels, resulting in a multiple-input multiple-output MIMO configuration....
- Tags: Technique, Georgia Institute Of Technology, Signal Processing, Broadband, MIMO-OFDM, OFDM, Productivity, Wireless
- White papers 2004-02-04
- On MIMO Signal Processing for Adaptive W-CDMA and OFDM Wireless Transceivers
- This paper considers wideband extensions of narrowband signal processing techniques for MIMO wireless transceivers. The extensions are applied and analyzed on commonly used wideband systems such as W-CDMA and OFDM. The paper focuses on signal processing techniques for channel estimation and correction, including pilot-aided and decision-directed LMS-based adaptive estimation. Simulation...
- Tags: W-CDMA, Signal Processing, MIMO, OFDM, Cellular Phones, Wireless, Consumer Electronics, Personal Technology
- White papers 2004-12-23
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