PXI WLAN Measurement Suite Data Sheet

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1 PXI WLAN Measurement Suite Data Sheet The most important thing we build is trust Bench-top R&D and production ready ATE RF performance verification tools Multi device parallel testing for higher production throughput MIMO test configurations for either R&D or production All DSSS, OFDM, non HT, HT and VHT frame formats Transmit power, modulation and spectral measurements CCDF, CW frequency and average power, OBW, ACLR Receiver sensitivity testing DSSS and OFDM equalization All channel bandwidths to 160 MHz The WLAN measurement suite is a collection of software tools for characterizing WLAN OFDM, DSSS and DSSS-OFDM RF signals during design validation or production test. The software is designed for use in conjunction with the PXI 3000 Series of RF modular instruments and performs measurements in accordance with the methods of IEEE (2012) and IEEE ac. Using the WLAN measurement suite with PXI 3000 RF modular instruments helps to accelerate new product introduction and increase test speed to lower the cost of test.

2 The measurement suite coupled with the excellent performance of PXI 3000 RF modules is ideal for characterizing WLAN devices during design validation and production test stages. Whether testing SISO or MIMO devices, either on the bench in R&D or in high volume automated production lines, the WLAN measurement suite provides the ideal user interface and level of control. PXI Studio 2 provides a user interface for bench-top manual operation during design integration or trouble shooting with multiple views of graphical traces. PXI Maestro is a turnkey production ATE solution optimized for test speed complete with integrated device and external PSU control to enable rapid deployment into production lines. Measurement and analysis component libraries provide low level remote programming interfaces for highly customized ATE system integration. IQCreator WLAN waveform generation tools (supplied separately), enable generation of bespoke test waveforms for use in testing receiver sensitivity or RF component test characterization. Figure 1. Measurement Suite Software Component Architecture IQCreator, PXI Maestro and PXI Studio 2 application software is supplied free of charge with all PXI 3000 modules. Operation of the WLAN measurement suite or IQCreator requires simple activation of a license key option on the PXI 3000 hardware. Further information for these applications is available through the following links: IQCreator PXI Studio PXI Maestro

3 Figure 2.1. PXI Studio 2 example screenshot Figure 2.2. IQCreator example screenshot

4 WLAN Demodulation and Signal Analysis Figure 2.3. PXI Maestro example screenshot Coding scheme, data rate and modulation type are determined automatically from preamble and header decoding, thus requiring minimal user set-up making using the measurement library easy to operate and integrate within a test application. Equalization for pilot time, amplitude and phase tracking can be configured by the user. All modulation and coding schemes are supported (MCS) for HT and MCS 0 9 for VHT. 1 MCS and require PXI RF Combiner model 3066 to be used) Measurements are as described in the relevant clauses of either IEEE (2012) or IEEE ac as summarized in table 1 below. Non HT HT VHT Measurements 1 & 2 Mbps DSSS 5.5 & 11 Mbps OFDM Tx Power / Tx Power on and off ramp NA Transmit Spectral Mask Spectral Flatness NA Transmit Center Frequency Tolerance Chip/Symbol Clock Frequency Tolerance Transmit Center Frequency Leakage Transmit Modulation Accuracy / Constellation Error / /4 Receiver Minimum Input Level Sensitivity (1) Receiver Maximum Input Sensitivity (1) Table 1. IEEE (2012) and IEEE802.11ac Measurement Clauses (1) See hardware configuration table in specification. When used with test sequencing options for 3030 Series or 3070A (option 203) all required waveforms are generated within the PXI Maestro application. In all other use cases the waveforms can be created using IQCreator in which case 3020 or 3320 option 100 is required.

5 MIMO PXI 3000 can be configured in various ways to support MIMO testing on WLAN devices Production ATE The most economical MIMO test methods use either a composite or a switched technique requiring just one VSA and VSG and a RF Combiner switch module. The combiner choice is dependent on which MIMO method you elect to use. PXI 3061 or PXI 3066 can provide connection ports for up to 3 or 4 antennas respectively and support either switched or composite MIMO techniques. Alternatively 3065A can be used in conjunction with a passive RF power splitter/combiner for composite MIMO technique alone. True MIMO R&D Figure 3. 4x4 MIMO test configuration for production ATE True MIMO testing is supported using PXI 3070A VSA and PXI 3050A VSG module variants. This method of test is ideally suited for R&D testing using a separate VSA, VSG for each antenna / stream. Each channel can be configured with VSG out and VSA in ports or with a RF COM port by adding a separate PXI 3065A RF Combiner module. Signal Generators Signal Analyzers MIMO connections Comment Economical and fast Figure 4. PXI chassis configured for 2x2 MIMO (shown without 3065A PXI RF combiner). Add a 2nd chassis for 4x4 MIMO

6 Figure 5. PXI chassis configured for 3x3 MIMO (without PXI RF combiner) Switched True Composite VSG 3025C/3026C (1) 3050A (3) /3320 VSA 3035C/3036 (4) 3070A Combiner 3061 (2) A (2) Table 2a. Recommended Module Selection vs MIMO technique HT/VHT (80, 80+80) Note C/3026C are not suitable for generating VHT 160 MHz 2. Requires an additional external passive power combiner/splitter 3. Add option 04 (High output power), when required to support RX maximum input level sensitivity testing in conjunction with 3061 RF combiner or test systems with high path losses. 4. Requires option 114 when measuring VHT 160 MHz

7 SPECIFICATION All specifications for accuracy and operating range relate to use in conjunction with a 3030 Series or 3070A PXI RF Digitizer with option 113 and/or option 103 fitted operating in 2.4 GHz and 5 GHz ISM band.. All specifications relating to 160 MHz bandwidth signals are when using 3070A or 3035C/3036 with option 114 enabled. Measurements are in accordance with the methods of IEEE (2012) and IEEE ac standards. Specifications are defined with the input signal at the RF Digitizer tuned frequency and at the reference level unless otherwise stated. Where applicable measurement results are available for each antenna, each stream and in the case of MHz for each segment, (primary or secondary). Measurements are supported for SISO or MIMO using either a single RF Digitizer or multiple 3070A RF Digitizers. MIMO testing for up to 3x3 using a single RF Digitizer with either PXI Studio 2 or PXI Maestro requires use of either a 3061 or 3066 PXI RF Combiner. MIMO testing for 4x4 using a single RF Digitizer with either PXI Studio 2 or PXI Maestro requires use of a 3066 PXI RF Combiner. Use of PXI Maestro requires a PXI 3000 Series RF Digitizer*, RF Signal Generator* and optionally an RF Combiner module Use of PXI Studio requires a PXI 3000 Series RF Digitizer* *plus any associated RF synthesizer module where necessary CONFIGURATION The WLAN measurement suite supports demodulation of eitiher IEEE standard compliant or non standard PSDU formats. Automatic setting of system type (OFDM/DSSS/DSSS-OFDM), data rate, data length, modulation type is decoded from header information. For HT and VHT signals, this also includes MCS index and requires user setting for bandwidth Analysis Mode a/b/g (note j/p requirements are served as a subset of a) n HT (High Throughput), n non-ht ac VHT (Very High Throughput (2) ), ac HT (HT signal in 80 MHz bandwidth), ac non-ht (2) Channel Bandwidth 5, 10, 20, 40, 80, and 160 (3) MHz Channel Offset (802.11n and ac only) None, Upper 1 to 4, Lower 1 to 4 Auto BSS (basic service set) Bandwidth (802.11n and ac only) Enable or disable. When disabled, BSS bandwidth can be defined by user. Auto Detect Number of Symbols to Analyze On/Off 11ac VHT analysis data length derivation is user selectable from ALL, SigB, Lsig or BurstEdges Number of Symbols OFDM: DSSS: 1 to packet length 16 to packet length DSSS Reference Filter (802.11b and g) None, Rectangular, Raised Cosine,(alpha 0 to 1.0), Gaussian (BT 0.05 to 1.0) Antenna Settings Antenna: 1-8. This specifies the index of the antenna that you wish to measure Antenna segment: Select which segment of a given antenna to be measured. Only available in VHT MHz mode Compensation Pilot time tracking, on/off Pilot amplitude tracking, on/off Pilot phase tracking, on/off

8 Equalization DSSS: Enable/disable Filter length range 3 to 99 (odd integer values) OFDM: Pre-amble Pre-amble plus pilots and data Burst Profile Type Average power or peak power MIMO Mode Selection Switched (requires association with 3061/3066 RF Combiner) Composite True (Requires association with a separate RF Digitizer per Tx chain) MEASUREMENTS The results are available for live, average, min hold, max hold, std dev. POWER Transmit Power (dbm) The Peak and RMS power is measured for a single PPDU Accuracy See 3030 Series and 3070A module level accuracy spec Burst Length (μs) The burst length is the time between the rising and falling edge of a single PPDU burst Rising / Falling Edge Time (DSSS) Measures the power ramp up and power ramp down times for a single PPDU Reference Results are relative to either the Peak or Average power of the PPDU Indication Global pass/fail Ramp up pass/fail Ramp up time in μs (10% to 90% points) Ramp down pass/fail Ramp down time in μs (90% to 10% points) Burst position μs relative to trigger point Trace Power vs.time trace

9 SPECTRAL EMISSION MASK The spectral density of the transmitted PPDU signal is measured with respect to the spectral mask corresponding to power class A. With spectrum analysis mode set Analyze Burst an external burst trigger may be required depending upon the RF Digitizer variant used and the bandwidth of the signal as per table 3. The mask is frequency aligned to the maximum spectrum density. Mask types a (5, 10 and 20 MHz Bandwidths) b n (2.4 GHz and 5 GHz bands) ac (2) User defined MHz SEM measurement is unsupported using 3035C RF Digitizer where segments occupy channels 106 and 155 Measurement BW 100 khz Indication Global pass/fail The worst case dbc level value and its corresponding frequency relative to the mask. Accuracy (nominal error relative to mask) ±0.05 db per 10 db excluding the effects of noise floor Trace Spectral trace display with mask The trace display is formed from FFT stitching. Table 3 indicates the number of stiches required as a function of bandwidth and RF Digitizer variant. HR/DSSS Frame Format OFDM, HT and VHT Channel Bandwidth 20 MHz 40 MHz 80 MHz 160 MHz Minimum Measurement Span 44 MHz 60 MHz 120 MHz 480 MHz RF Digitizer variant 3030A C 3035C 3036 Maximum Aquisition Bandwidth Theoretical No. of acquisitions required for the Minimum Measurement Span 36 MHz 2 2 NA 90 MHz (>1 GHz) NA A 160 MHz (>900 MHz with option 5) Table 3. Acquisitions required to accumulate the required measurement span vs. RF Digitizer variant and modulation bandwidth OCCUPIED BANDWIDTH (OBW) Bandwidth (Hz) containing 99% of total of the transmitted PPDU energy Accuracy Typically <100 khz

10 ADJACENT CHANNEL POWER (FOR DSSS SIGNALS) The power (dbc) measured in the upper and lower adjacent and alternate channels relative to the power in the reference channel. Reference Channel Bandwidth 22 MHz Adjacent and Alternate Channel Bandwidth ±11 MHz, ±22 MHz Measurement Range Typically 65 db for IEEE b 11 Mbps CCK Accuracy (nominal) ±0.05 db error per 10 db excluding the effects of noise floor MODULATION ACCURACY/CONSTELLATION ERROR The error vector magnitude (EVM) or RCE (Residual Constellation Error) is measured relative to the ideal constellation point. EVM Composite EVM (4) (% rms) and RCE (rms db) EVM (% rms) and RCE (rms db) all data carriers EVM (% rms) and RCE (rms db) all pilot carriers EVM (Peak) b/g only For MIMO test conditions EVM results are also available per antenna and per stream Accuracy (Results based on the highest order modulation and the maximum modulation symbol rate for the given bandwidth) Frequency Bandwidth GHz MHz Standard Input (dbm) b g/n 0.2% -51 db n 0.8% -41 db j/p a/n n % -42 db ac 0.8% -41 db % -42 db 0.7% -42 db 0.7% -42 db 0.7% -42 db 1.2% -38 db Table 4. Combined nominal residual RMS EVM (%) / RCE (db) when 3025C/3026C is used as input to 3035C Levels above -10 dbm are valid for 3026C only.

11 Frequency GHz Bandwidt h MHz Standard Input Power b g/n -48 db 0.2% -52 db -48 db -48 db 0.8% -41 db n 1.2% -38 db j/p 1.2% -38 db a/n 1.2% -38 db n -48 db 1.5% -36 db Table 5. Combined nominal residual RMS EVM (%) / RCE (db) when 3025C/3026C is used as input to 3030A and Levels above -10 dbm are valid for 3026C only. FrequencyBandwidth GHz MHz Std RF Input Power (dbm) b g/n 0.10% -60 db 0.13% -58 db 0.10% -60 db 0.13% -58 db 0.10% -60 db 0.16% -56 db 0.10% -60 db 0.16% -56 db 0.16% -56 db 0.19% -54 db n 0.18% -55 db 0.18% -55 db 0.22% -53 db 0.22% -53 db 0.26% -52 db j/p a/n 0.33 % 0.33% 0.33 % 0.33% 0.34 % 0.34% 0.34 % 0.34% 0.36 % 0.36% n 0.32% 0.33% 0.35% 0.36% 0.40% -48 db % 0.31% 0.32% 0.32% 0.35% ac 0.33% 0.40% -48 db 0.32% 0.40% -48 db 0.34% 0.45% 0.34% 0.44% 0.39% -48 db 0.51% % 0.48% 0.57% 0.56% 0.65% (Equalisation method used: data & pre-amble) Table 6. Combined nominal residual RMS EVM (%) and RCE (db) when 3050A is used as input to 3070A or 3035C/3036 with option 114 enabled Traces Measured constellation relative to the ideal constellation EVM % values vs. sub carrier or symbol number General Information Derived from Demodulation System type, modulation type, data rate, number of PSDU bits/symbols, HT format (Greenfield or Mixed), n HT mode only, short GI (11n/ac only)

12 FREQUENCY ERROR TOLERANCE Frequency error (Hz) measurement for PPDU Lock Range ±50 ppm up to a maximum of ±312.5 khz Accuracy <±10 Hz + (Freq standard error transmitter freq (MHz)) Trace Frequency error vs. time across preamble SYMBOL/CHIP CLOCK TOLERANCE Range ±50 ppm Accuracy As per reference frequency SPECTRAL FLATNESS (FOR OFDM SIGNALS) Indication Pass/fail Upper pass/fail Lower pass/fail Trace dbr vs. sub carrier and mask MIMO SPECIFIC RESULTS HT/VHT (2) CROSS POWER Indication dbm up to eight spatial streams CHANNEL MATRIX Indication Matrix of complex elements for numstreams x numantenna (where streams=antenna), averaged overall sub-carriers CHANNEL MATRIX CONDITION NUMBER Vs. SUB CARRIER Trace Representation of the channel matrix condition for each sub-carrier Value displayed as 1 or higher where 1 = ideal conditioning CHANNEL FREQUENCY RESPONSE Vs. SUB CARRIER Trace ±dbr vs. sub-carrier for the specified antenna and stream GENERAL MEASUREMENT CW Frequency and Power CCDF Complimentary cumulative distribution function Trace Peak to average power (db) vs. probability (%) (2) Require 3030 or 3070A option 113 (3) Requires 3070A with option 03 and 05 or 3035C/3036 with option 114 (4) Support for Nss = 2 or higher requires the use of an 3061 RF combiner

13 RX MEASUREMENTS (PXI MAESTRO) Receiver measurements additionally require either 3020 Series or 3050A/3320 RF Signal Generator. PXI Maestro supports waveform generation in accordance with the requirements of table below. Alternatively IQCreator can be used to generate the required waveforms for use outside of PXI Maestro or 3320 option 100 is required to play waveforms designed using IQCreator. VHT signals with bandwidths of 160 MHz require PXI 3320 module fitted with option MHz bandwidth signals are not compatible with 3020 Series RF Signal Generator. Test Case Format reference HR/DSSS Receiver Minimum Input Level Sensitivity OFDM HT VHT HR/DSSS Receiver Maximum Input Level OFDM HT VHT Table 7. PXI Maestro Receiver Test Cases Receiver Maximum Input Level Sensitivity Hardware compatibility for maximum input sensitivity testing is dependent on the path loss to the device antenna and the VSG peak RF output level. The table below indicates which PXI VSG module variant and option configuration should be selected when used in conjunction with 3065A, 3061 or 3066 PXI RF combiner module. Refer to the 3020 Series and 3050A module data sheets for details concerning the VSG - maximum peak RF output power. Frame Format Test Clause Receive Input Level (dbm) 3020 Series and 3050A Compatibility when using 3061, 3065A or 3066 RF Combiner A/3066 HR/DSSS OFDM 2.4 GHz C, 3026C, 3050A Any 5 GHz C, 3050A 3025, 3025C, 3026C, 3050A Table 8. Rx Max Input Sensitivity Compatibility

14 GENERAL CPU Operating System Windows 7/32 bit or 7/64 bit Required CPU Memory 512 Mbytes minimum, 1024 Mbytes recommended Display Resolution Minimum Hardware Compatibility IEEE Standard Module Type Module Variant Option Carrier Frequencies up to 3 GHz Carrier Frequencies up to 6 GHz Bandwidth True MIMO (2) Composite or Switched (3) MIMO 3020A 20 MHz 40 MHz <20 MHz 40 MHz 80 MHz MHz 160 MHz 3020C Signal Generation 3021C (8) C 3026C (8) 3050A (9) 05 (5) (5) (5) (5) (5) (6) 3030A 3030C Signal Analysis C (4) (4) (4) (4,10) (4) 3036 (4) (4) (4) (4) (4) 3070A 103 (4,5) (4,5) (4,5) (4,5) (4,5,7) Table 9. Summary of PXI Module Compatibility Notes 1. Deliberately left blank A is recommeded 3. Refer to table 2 for RF combiner recommendation 4. Add option 113 for ac VHT 5. Add option 03 Frequency extension to 6 GHz and add option 114 if using 3035C/ Add option 03 Max sampling rate increased to 250 MHz 7. Add option MHz Bandwidth 8. Required if performing Rx max input sensitivity test with 3061 or 3065A 9. Add option 04 if performing Rx max input sensitivity test with 3061 Software Compatibility PXI 3000 Series modules require NI VISA version 4.6 or later ac (3030 option 113) requires PXI Studio2 version 2.1 or later ac (3070 option 113) requires PXI Studio2 version 2.2 or later and PXI module driver software or later Switched/composite MIMO operation with PXI 3066 requires driver version or later

15 ORDERING PXI 3000 Series Module Type Option Description 3030A/3030C/ C/ A WLAN a/b/g/n 3030 option option 103 WLAN ac Not compatible 3030 option 113** 3070 option 113* Connectively test sequencing with PXI Maestro 3030 option 203* 3070 option 203* Retrofit WLAN a, b, g, n RTROPT103/3030 RTROPT113/3070 Retrofit WLAN ac Not compatible RTROPT113/3030* RTROPT113/3070* Retrofit Connectivity Test Sequencing RTROPT203/3030* RTROPT203/3070* * Requires opt 103 ** Requires opt 103 and option 114 for VHT 160

16 Cobham Wireless - Validation Part No.46891/470, Issue 11, 07/15