antenna diversity

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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

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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, 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, Cyclic Delay Diversity, OFDM, Wireless

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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

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

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, Analysis, Productivity, Wi-Fi, Wireless

White papers 2007-01-23

Techniques for Bluetooth Performance Improvement

This paper examines the application of some techniques in Bluetooth communications expected to improve system's performance under certain environmental conditions. The transmitter diversity Alamouti scheme and receiver diversity have been evaluated and compared to the standard single antenna transmitter and receiver system by means of the achievable BER. Some analytical...

Tags: Technique, Transmitter, Bluetooth, Productivity, Wireless

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A Novel Compact Cable-Fed Antenna for a GSM/DCS Handset

By using a branch-line ground plane, a monopole radiator, and parasitic patches, a newly compact cable-fed antenna is investigated in order to overcome the thickness problem of the Planar Inverted-F Antenna PIFA. The designed antenna has dimensions of only 40 12 1 mm and the impedance bandwidth of the proposed...

Tags: John Wiley & Sons Inc., Antenna, Patches, Cellular Phones, Consumer Electronics, Personal Technology

White papers 2005-09-05

Miniaturized Printed Wire Antenna for Wireless Communications

In this paper miniaturized printed-circuit-board wire antennas are investigated for wireless local access network WLAN and Bluetooth applications. The proposed wire antenna in F-shape could have a much smaller area than an inverted F antenna with a similar bandwidth. It is found that F-antenna can usually be inductively tuned but...

Tags: Bandwidth, Wireless Communication, Antenna, Bluetooth, Wi-Fi, Wireless

White papers 2005-08-09

iTunes Antenna (widget)

iTunes Antenna displays the iTunes store's top songs, albums, new releases, and so on. If you click a list item, iTunes Antenna will show details and artwork. This version is the first release on CNET Download.com.

Tags: Apple iTunes, Digital Music, Digital Media, Personal Technology, Consumer Electronics

Software downloads 2007-05-30

Printed Straight F Antennas for WLAN and Bluetooth

Miniaturized printed-circuit-board antennas are proposed in PCMCIA cards for WALN and Bluetooth applications. The proposed antenna is a straight F in shape printed on a FR4 substrate together with the rest of the circuit components, providing a low-cost antenna solution. The straight F antenna resembles a printed inverted F antenna,...

Tags: WLAN, Antenna, F Antenna, Bluetooth, Wireless LANs, LANs, Wi-Fi, Wireless, Networking

White papers 2003-01-15

A Novel Microstrip Patch Antenna With Large Impedance Bandwidth in VHF/UHF Range

In this paper a novel antenna is presented. This antenna, employing microstrip circular disc as radiator is seen to perform over a large impedance bandwidth (130MHz to 876 MHz). The disk resonator is loaded with L-C-R circuit across a selective location in the disk via a thin shorting pin. The...

Tags: Bandwidth, Disk, Antenna, Disk Resonator

White papers 2006-01-09

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: Performance, Environment, Improvement, University Of Texas, Performance Management, Human Resources, Workforce Management

White papers 2005-04-14

An Open Access Wideband Multi-Antenna Wireless Testbed With Remote Control Capability

This paper introduces an open access wideband multi-antenna wireless testbed. The testbed is configured as a four transmit antenna by four receive antenna system based on software defined radio technology. It operates in the 2.4GHz ISM band and supports an RF bandwidth compatible to IEEE 802.11a/g standard. A robotic positioning...

Tags: Microsoft Access, Positioning, Radio, University Of California, Testbed, Branding, Advertising & Promotion, Marketing

White papers 2004-11-29

Transmit Selection Diversity for Unitary Precoded Multiuser Spatial Multiplexing Systems With Linear Receivers

Multiuser spatial multiplexing is a downlink transmission technique that uses linear transmit pre-coding to multiplex multiple users and pre-cancel inter-user interference. In such a system the spatial degrees of freedom are used for interference mitigation and generally come at the expense of diversity gain. This paper proposes two pre-coding methods...

Tags: Diversity, IEEE, Productivity, Wi-Fi, Wireless

White papers 2005-08-17

Mobile Wireless Communication System Antennas for 260 MHz-Band

Automotive mounted antennae are often vertically orientated 1/4 wave antennae because the body of the car can be used as an effective reflective infinite ground plane. The 1/4 wave antenna has a low cost and is also compact in size. This compact quality is important in automobile mounted antennae because...

Tags: Mobile, Wireless Communication, Antennae, Antenna, Wi-Fi, Wireless, Advertising & Promotion, Marketing

White papers 2006-03-26

Reconfigurable Antenna Solution for MIMO-OFDM Systems

A reconfigurable microstrip dipole antenna solution for Multiple Input Multiple Output MIMO communication systems making use of Orthogonal Frequency Division Multiplexing OFDM is presented. When applied to closely spaced antenna arrays, this method can increase link capacity. The benefits of this novel antenna solution are demonstrated by channel capacity measurements...

Tags: Drexel University, MIMO-OFDM, Antenna Solution, OFDM, Wireless

White papers 2006-01-23

Antenna Selection in High-Throughput Wireless LAN

This paper presents a new method for implementing antenna selection in high-throughput Wireless LANs WLANs, addressing two major practical concerns: antenna selection training protocol design, and calibration to solve RF imbalance problems. Specifically, the low Doppler spread of WLAN channels enables us to train all antenna subsets by multiple training...

Tags: WLAN, Training, Antenna Selection, Wireless LANs, LANs, Workforce Management, Wi-Fi, Wireless, Networking, Human Resources

White papers 2006-03-23

Smart Antenna Systems

A smart antenna system combines multiple antenna elements with a signal-processing capability to optimize its radiation and/or reception pattern automatically in response to the signal environment.What does an antenna do in a telecommunications system? It is the port through which radio frequency RF energy is coupled from the transmitter to...

Tags: International Engineering Consortium, Radio Frequency, Signal Processing, Telephony, Network Technology, Networking

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