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Agilent in Wireless Communications Webcast Series
Next Generation 802.11ac WLAN MIMO Design & Test Challenges
May 10, 2012; 10:00 AM PT/ 1:00 PM ET/ 5 PM UTC
The proliferation of Wireless LAN into new applications outside of the traditional email and browsing applications is driving the need for higher data rate throughput. New applications such as wireless display, HDTV streaming/distribution, and rapid upload/download of data are driving two new IEEE WLAN standards requirements for very high throughput: 802.11ac for frequencies below 6 GHz and 802.11ad for the 60 GHz band.
A goal of 802.11ac is to support wireless distribution of multiple multimedia/data streams with data rates of at least 1 Gbps in the 5 GHz band. Some key features for increasing data throughput are wider channel bandwidths (e.g. contiguous 80 MHz and 160 MHz, or non-contiguous 80+80 MHz), higher-order modulation with optional support for 256 QAM, and Multiple-Input Multiple-Output (MIMO) support for multiple spatial streams using multiple antenna techniques. Pre-distortion and beamforming are some further possibilities for high-performance systems. This challenging combination of wider bandwidths, higher-order modulation, and MIMO introduces new design and test challenges for the system engineer.
This presentation will show how the system engineer can use design simulation to help understand the design performance and design requirements needed to achieve transmitter system-level metrics such as EVM. System performance budget trade-offs can quickly and easily be performed with system design simulation tools, before designing hardware. Once hardware is available and prototype and R&D testing phase has begun, system simulation tools can then be combined with Arbitrary Waveform Generators (AWGs) to generate wide-bandwidth 160 MHz waveforms for MIMO testing. Multi-channel phase-coherent high performance digital oscilloscopes with Vector Signal Analysis (VSA) software are then used to perform the SISO or MIMO demodulation to evaluate the transmitter’s performance. In addition, the error contributions along the transmitter chain (IQ, IF, RF) can be measured using a digital oscilloscope with VSA software to help the system engineer optimize the design performance of the prototype hardware. This presentation will also show how simulation can be combined with test equipment to perform 802.11ac coded BER measurements on receiver DUT hardware.