Test and Measurement

Waveform generation, visualization, and performance analysis

Generate waveforms and use quantitative tools to measure system performance. Use graphical utilities such as constellation and eye diagrams to visualize the effects of various impairments and corrections.

Apps

Wireless Waveform Generator	Create, impair, visualize, and export modulated waveforms
BER Analyzer	Analyze bit error rate (BER) performance of communications systems

Functions

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Bit Error Rate Calculation and Estimation

`biterr`	Number of bit errors and bit error rate (BER)
`symerr`	Compute number of symbol errors and symbol error rate
`berawgn`	BER and SER for uncoded AWGN channels
`bercoding`	Bit error rate (BER) for coded AWGN channels
`berconfint`	Bit error rate (BER) and confidence interval of Monte Carlo simulation
`berfading`	Bit error rate (BER) for Rayleigh and Rician fading channels
`berfit`	Fit curve to nonsmooth empirical bit error rate (BER) data
`bersync`	Bit error rate (BER) for imperfect synchronization
`semianalytic`	Calculate bit error rate (BER) using semianalytic technique

Visualization

`scatterplot`	Generate scatter plot
`eyediagram`	Generate eye diagram
`plotPhaseNoiseFilter`	Plot response of phase noise filter block

Utilities

`marcumq`	Generalized Marcum Q function
`noisebw`	Equivalent noise bandwidth of filter
`qfunc`	Q function
`qfuncinv`	Inverse Q function
`showcommblockdatatypetable`	Communications Toolbox block characteristics

Objects

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Measurements

`comm.ACPR`	Adjacent Channel Power Ratio measurements
`comm.CCDF`	Measure complementary cumulative distribution function
`comm.ErrorRate`	Compute bit or symbol error rate of input data
`comm.EVM`	Measure error vector magnitude
`comm.MER`	Measure modulation error ratio

Visualization

`comm.ConstellationDiagram`	Display constellation diagram for input signals
`dsp.SpectrumAnalyzer`	Display frequency spectrum of time-domain signals
`timescope`	Display time-domain signals
`dsp.ArrayPlot`	Display vectors or arrays

Blocks

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Measurements

Error Rate Calculation	Compute bit error rate or symbol error rate of input data
EVM Measurement	Measure error vector magnitude
MER Measurement	Measure signal-to-noise ratio (SNR) in digital modulation applications

Visualization

Constellation Diagram	Display constellation diagram for input signals
Eye Diagram	Display eye diagram of time-domain signal
Time Scope	Display and analyze signals generated during simulation and log signal data to MATLAB
Spectrum Analyzer	Display frequency spectrum

Topics

Bit Error Rate (BER)

Obtain numerical evaluation results.

Adjacent Channel Power Ratio (ACPR)

Adjacent channel power ratio (ACPR) calculations (also known as adjacent channel leakage ratio (ACLR)), characterize spectral regrowth in a communications system component, such as a modulator or an analog front end.

Error Vector Magnitude (EVM)

EVM Measurements.

Scatter Plots and Constellation Diagrams

Generating scatter plots.

Visualize RF Impairments

Apply various RF impairments to a QAM signal.

Plot Signal Constellations

This example shows how to plot a PSK constellation having 16 points.

Eye Diagram Analysis

In digital communications, an eye diagram provides a visual indication of how noise might impact system performance.

Selected Bibliography for Measurements

List of references for further reading.

Featured Examples

BLE Blocking, Intermodulation and Carrier to Interference Performance Tests

Model Bluetooth® low energy (BLE) RF-PHY receiver tests specific to blocking, intermodulation and carrier to interference (C/I) performance as per the Bluetooth RF-PHY Test Specifications [ 1 ] using Communications Toolbox™ Library for the Bluetooth Protocol.

Open Live Script

BLE Modulation Characteristics, Carrier Frequency Offset and Drift Test Measurements

Perform Bluetooth® low energy (BLE) radio frequency (RF) physical layer (PHY) transmitter tests specific to modulation characteristics, carrier frequency offset, and drift using Communications Toolbox™ Library for the Bluetooth Protocol. The test measurements compute frequency deviation, carrier frequency offset, and drift values. This example also verifies whether these test measurement values are within the limits specified by the Bluetooth RF-PHY Test Specifications [ 1 ].

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BLE Output Power and In-Band Emissions Test Measurements

Perform transmitter test measurements specific to output power and in-band emissions on Bluetooth (R) Low Energy (BLE) transmitted waveforms as per the Bluetooth RF-PHY Test Specifications [ 1 ] using Communications Toolbox™ Library for the Bluetooth Protocol.

Open Live Script

Bluetooth BR RF-PHY Transmitter Tests for Modulation Characteristics, Carrier Frequency Offset, and Drift

Perform Bluetooth® basic rate (BR) radio frequency (RF) physical layer (PHY) transmitter tests specific to modulation characteristics, carrier frequency offset, and drift using the Communications Toolbox™ Library for the Bluetooth Protocol. The test measurements compute frequency deviation, carrier frequency offset, and drift values. This example also verifies whether these test measurement values are within the limits specified by the Bluetooth RF-PHY Test Specifications [1].

Open Live Script

Bluetooth EDR RF-PHY Transmitter Tests for Modulation Accuracy and Carrier Frequency Stability

Perform Bluetooth® enhanced data rate (EDR) radio frequency (RF) physical layer (PHY) transmitter tests specific to modulation accuracy and carrier frequency stability using the Communications Toolbox™ Library for the Bluetooth Protocol. The test measurements compute the initial frequency offset, root mean square (RMS) differential error vector magnitude (DEVM), and peak DEVM values. This example also verifies whether these test measurement values are within the limits specified by the Bluetooth RF-PHY Test Specifications [1].

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Link Budget Analysis

In the design of wireless communications links between two sites, issues of range, throughput, and received signal quality are of critical importance to the system engineer. Link budget analysis accounts for all gains and losses in the communication link. Some factors and design choices, such as propagation path length, signal polarization, and antenna feed cable, degrade signal quality, while others, such as the power amplifier and antenna size, can increase transmitted signal strength.

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EVM Measurements for a 802.15.4 (ZigBee®) System

Use the comm.EVM System object™ to measure the error vector magnitude (EVM) of a simulated IEEE® 802.15.4 [ 1 ] transmitter. IEEE 802.15.4 is the basis for the ZigBee specifications.

Open Script