Constellation Diagram

在智商平面中显示和分析输入信号

李brary:
Communications Toolbox / Comm Sinks
通信工具箱HDL支持/通讯下沉万博1manbetx

Description

The Constellation Diagram block displays real- and complex-valued floating- and fixed-point signals in the IQ plane. Use this block to perform qualitative and quantitative analysis on modulated single-carrier signals. Specifically, the IQ-plane displays the in-phase and quadrature components of modulated signals on the real and imaginary axis of an xy-plot.

Constellation diagram displaying QSPK,16-QAM, and 8-DPSK signals, and signal quality measurements.

在“星座图”窗口中，您可以：

在单个星座图上输入和绘制多个信号。要为每个输入信号定义一个参考星座，请使用Reference Constellationparameter.
Select signals in the legend to toggle visibility of individual channels. To display the legend, use theLegendparameter on thePlot标签。对于多通道信号，将输入指定为矩阵，其矩阵列中定义的单个信号。
Display calculated error vector magnitude (EVM) and modulation error ratio (MER) measurements for individual signals. To view and configure the measurements, selectEVM/MER上theMeasurements标签。When multiple signals are input, you can select which signal to use for measurements in theChannelsection.

Ports

Input

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`in_1，...，in_n`- 信号（作为单独的端口）
column vectors | matrices

信号，指定为单独的参数N_sym-by-1 column vectors orN_sym-by-N_channelmatrices.N_sym是符号的数量，并且N_channel是个number of input signal channels. Signals can have different data types and dimensions.

You must specifyN输入端口，其中N是个Number of input ports参数值。You can visualize up to 20 individual or collective signal channels in the constellation diagram. For example, if you create a two-channel signal for every input, then you can define up to 10 input ports.

Example:[-1 + 1i; -1 - 1i; 1 + 1i; 1 - 1i]指定四符号输入信号。

数据类型:double
Complex Number Support:Yes

Parameters

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Plot

在里面Plottab, you can adjust settings of the constellation diagram configuration, simulate the model, take a snapshot of the plot, copy the display, and print the figure. Parameters unique to the constellation diagram scope are described.

`Settings`— Constellation diagram settings
button

在Plottab, clickSettings打开配置图设置窗口。此窗口包括参数小节，以配置数据和轴，标签以及颜色和样式。星座图独有的参数在此页面上描述。

`Number of input ports`- 示波器块上的输入端口数
`1`（默认）|integer in the range [1, 20]

指定示波器块上的输入端口的数量作为整数[1，20]。

输入信号通道的总数不能超过20。当您指定多通道输入信号时，输入信号通道的总数会限制输入端口的最大数量。

`每个符号样本`— Number of samples used to represent each symbol
`1`（默认）|正整数

指定用于表示每个符号为正整数的样品数量。信号在绘制该参数的值之前被信号降采样。

`Offset`— Number of samples to skip before plotting points
`0`（默认）|不nnegative integer

Specify the number of samples to skip before plotting points as a nonnegative integer less than the每个符号样本参数值。此值指定在每个符号样本is greater than 1.

`Symbols to display`- 显示的最大符号数量
`Input frame length`（默认）|正整数

Specify the maximum number of symbols to display by selectingInput frame length或者specifying a positive integer. To specify a positive integer, select and then replace带有您所需的价值。Use this parameter to limit the maximum number of symbols that the constellation diagram displays when you input long signals. The block plots the most recently received symbols.

`Reference Constellation`— Reference constellation configuration
button

在Plottab orMeasurementstab, clickReference Constellation，打开参考星座窗口。此窗口包括用于配置每个输入端口的参考星座的参数。

`显示参考星座`— Option to display reference constellations
`上`（默认）|`off`

Select this parameter to show reference constellations on the plot.

`Input`— Select input port
1 (default) | positive integer

Configure the reference constellation parameters for the specified input port.

每个输入端口都有其自己的参考星座。对于多通道输入信号，该块为该输入端口中的所有信号应用了单个参考星座。

`Reference constellation`— Reference constellation
`Custom`（默认）|`BPSK`|`8-PSK`|`16 Qam`|`64-QAM`|`256-QAM`

Specify the reference constellation by selectingCustom,BPSK,QPSK,8-PSK,16 Qam,64-QAM，或者256-QAM. To specify a custom value, first selectCustom. Then in the自定义值参数，用符号值的自定义向量替换条目。

每个输入端口都有其自己的参考星座。对于多通道输入信号，该块为该输入端口中的所有信号应用了单个参考星座。

EVM/MER测量使用指定的参考星座来计算调制输入信号的信号质量。有关信号质量测量的更多信息，请参见EVM和MERMeasurements.

`自定义值`— Input reference constellation
`[0.7071+0.7071I -0.7071+0.7071I -0.7071-0.7071I 0.7070-0.7071I]`（默认）|vector

Specify the reference constellation for an input as a vector that defines symbol values for the custom modulation scheme.

依赖性

To enable this parameter, set theReference constellation参数为自定义参考星座.

数据类型:char|double
Complex Number Support:Yes

`Constellation normalization`— Normalization method
`平均功率`（默认）|`Minimum distance`|`峰值功率`

通过选择该块用于星座图的归一化方法平均功率,Minimum distance，或者峰值功率.

依赖性

To enable this parameter, set theReference constellation参数为16 Qam,64-QAM，或者256-QAM.

`平均参考功率`— Average power of reference constellation
`1`（默认）|positive scalar

Specify the average power of the reference constellation as a positive scalar. The average power is referenced to a one-ohm load. Units are in watts.

依赖性

To enable this parameter, set theReference constellation参数为BPSK,QPSK,8-PSK,16 Qam,64-QAM，或者256-QAM.

`Reference phase offset (rad)`— Phase offset of reference constellation
标量

Specify the phase offset of the reference constellation as a scalar. Units are in radians.

依赖性

To enable this parameter, set theReference constellation参数为BPSK,QPSK,8-PSK,16 Qam,64-QAM，或者256-QAM.

The default value is0forBPSK,16 Qam,64-QAM, and256-QAM.
The default value ispi/4for8-PSK.
The default value ispi/8forQPSK.

`Legend`— Option to display legend
button

在Plottab, clickLegend要切换传说的显示。图例中列出的名称是模型中指定的输入端口的信号的名称。在模型使用输入信号运行之前，该图例不会显示。

在里面scope legend, click a signal name to toggle the signal visibility in the scope.

`Trajectory`— Option to display signal trajectory
button

在Plottab, clickTrajectoryto toggle the display of the trajectory. Select this parameter to display the trajectory between constellation points for the plotted signals.

Measurements

在里面Measurements选项卡，您可以选择活动频道，配置信号质量测量结果，然后切换Measurementspane.

有关信号质量测量的更多信息，请参见EVM和MERMeasurements.

Channel

`Channel`- 主动输入通道
name of first channel in first port (default) | list of channels

从输入通道列表中选择活动输入通道以进行测量。点击EVM/MERto display the signal quality measurements for the active channel.

输入信号通道的总数不能超过20。当您指定多通道输入信号时，输入信号通道的总数将限制该的最大允许值Number of input portsparameter.

Measurements

`Measurement Interval`— Duration of EVM and MER measurement
`当前显示`（默认）|`所有显示`| positive integer

Specify the duration of the EVM and MER measurement in symbols by selectingCurrent Display，或者所有显示或者by specifying a positive integer. To specify a positive integer, select and then replace带有您所需的价值。该值必须是范围内的正值[1，Symbols to display). The block computes measurements after the number of input data samples exceeds the measurement interval.

`EVM归一化`— Normalization method
`Average constellation power`（默认）|`Peak constellation power`

Specify the normalization method that the block uses for the EVM normalization by selectingAverage constellation power或者Peak constellation power.

`Reference Constellation`— Reference constellation configuration
button

在Plottab orMeasurementstab, clickReference Constellation，打开参考星座窗口。此窗口包括用于配置每个输入端口的参考星座的参数。有关参数说明，请参阅Reference Constellation参数Plotsection.

`EVM/MER`— Option to display signal quality measurements pane
button

在Measurementstab, clickEVM/MERto toggle display the signal quality measurements pane. For more information, seeEVM和MERMeasurements.

模型示例

View Constellation Diagram

使用星座图块可视化调制信号的星座。

Open Model

View Multi-Input Constellation Diagram

Use the Constellation Diagram block to visualize the constellation of multi-input and multichannel modulated signals.

Open Model

Add RF Impairments to DQPSK Signal

This model applies RF impairments to a signal modulated by differential quadrature phase shift keying (DQPSK). To demonstrate and visualize the RF impairments, levels applied in this model are exaggerated and not representative of typical levels for modern radios.

Open Script

Block Characteristics

数据类型	`Boolean`\|`double`\|`enumerated`\|`固定点`\|`integer`\|`单身的`
直接进料	`不`
Multidimensional Signals	`不`
Variable-Size Signals	`yes`
Zero-Crossing Detection	`不`

More About

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EVM和MERMeasurements

TheMeasurementspane displays the EVM and MER signal quality measurement settings and the calculation results for the specified signal channel.

EVM— An error vector is a vector in the IQ plane from the ideal constellation point to the actual point at the receiver. The EVM calculations include root mean square (RMS), peak, and average values.

您可以将EVM_RMS和EVM_Averagecalculations by the average or peak constellation power method as computed using these algorithms.

EVM归一化Method	Algorithm
Average constellation power	$E V M_{k} = 100 \sqrt{\frac{e_{k}}{P_{avg}}}$ EVM_RMS，以平均星座功率正常化为百分比： $E V M_{RMS} (%) = 100 \sqrt{\frac{\frac{1}{N} \sum_{k = 1}^{N} (e_{k})}{P_{avg}}}$
Peak constellation power	$E V M_{k} = 100 \sqrt{\frac{e_{k}}{P_{max}}}$ EVM_RMS，以峰值星座功率归一化为百分比： $E V M_{RMS} (%) = 100 \sqrt{\frac{\frac{1}{N} \sum_{k = 1}^{N} (e_{k})}{P_{max}}}$

EVM归一化Method

Algorithm

Average constellation power

$E V M_{k} = 100 \sqrt{\frac{e_{k}}{P_{avg}}}$

EVM_RMS，以平均星座功率正常化为百分比：

$E V M_{RMS} (%) = 100 \sqrt{\frac{\frac{1}{N} \sum_{k = 1}^{N} (e_{k})}{P_{avg}}}$

Peak constellation power

$E V M_{k} = 100 \sqrt{\frac{e_{k}}{P_{max}}}$

EVM_RMS，以峰值星座功率归一化为百分比：

$E V M_{RMS} (%) = 100 \sqrt{\frac{\frac{1}{N} \sum_{k = 1}^{N} (e_{k})}{P_{max}}}$

TheMeasurementspane shows the RMS and peakEVMin percent and the average and peakEVMdecibels for the selected input channel. TheEVM在分贝中计算为EVM(dB) = 10 ‑ log10(EVM_{多发性硬化症}）= 20 - log10（EVM_RMS), where:

$e_{k} = {(I_{k} - {\tilde{I}}_{k})}^{2} + {(Q_{k} - {\tilde{Q}}_{k})}^{2}$
I_k是个in-phase value of thek输入向量中的符号。
Q_k是个quadrature phase value of thek输入向量中的符号。
I_k和Q_krepresent ideal (reference) symbol values. ${\tilde{I}}_{k}$ 和 ${\tilde{Q}}_{k}$ represent measured (received) symbol values.
N是个input vector length.
P_avg是个value for average constellation power.
P_max是个value for peak constellation power.
$E V M_{RMS} = \sqrt{E V M_{多发性硬化症}}$

The maximumEVM向量中的价值是 $E V M_{max} = max_{k \in [1, ..., N]} {E V M_{k}},$ where k is the kth symbol in a vector of lengthN.

MER—MER是个ratio of the average power of the transmitted signal to the average power of the error vector. TheMeasurementspane indicates averageMER测量结果为所选信号通道的分贝。
MERis a measure of the SNR in a modulated signal, calculated in dB. TheMERoverN符号是

$M E R = 10 \cdot \log_{10} (\frac{\sum_{n = 1}^{N} (I_{k}^{2} + Q_{k}^{2})}{\sum_{n = 1}^{N} (e_{k})}) dB,$

where:
- $e_{k} = {(I_{k} - {\tilde{I}}_{k})}^{2} + {(Q_{k} - {\tilde{Q}}_{k})}^{2}$
- I_k是输入矢量中KTH符号的同相值。
- Q_k是个quadrature phase value of the kth symbol in the input vector.
- I_k和Q_krepresent ideal (reference) values. ${\tilde{I}}_{k}$ 和 ${\tilde{Q}}_{k}$ represent measured (received) symbols.

可编程配置

您可以通过使用示波器配置对象，以回调或脚本中的内部编程配置范围属性Control Scope Blocks Programmatically(Simulink).

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

当在包含此块的系统上执行代码生成时，将此块排除在生成的代码之外。

HDL Code Generation
Generate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.

该块可用于生成HDL代码的子系统中的模拟可见性，但不包括在硬件实现中。

Version History

Introduced in R2013b

Constellation Diagram

Description

Ports

Input

in_1，...，in_n- 信号（作为单独的端口）column vectors | matrices

Parameters

Plot

Settings— Constellation diagram settingsbutton

Number of input ports- 示波器块上的输入端口数1（默认）|integer in the range [1, 20]

每个符号样本— Number of samples used to represent each symbol1（默认）|正整数

Offset— Number of samples to skip before plotting points0（默认）|不nnegative integer

Symbols to display- 显示的最大符号数量Input frame length（默认）|正整数

Reference Constellation— Reference constellation configurationbutton

显示参考星座— Option to display reference constellations上（默认）|off

Input— Select input port1 (default) | positive integer

Reference constellation— Reference constellationCustom（默认）|BPSK|8-PSK|16 Qam|64-QAM|256-QAM

自定义值— Input reference constellation[0.7071+0.7071I -0.7071+0.7071I -0.7071-0.7071I 0.7070-0.7071I]（默认）|vector

依赖性

Constellation normalization— Normalization method平均功率（默认）|Minimum distance|峰值功率

依赖性

平均参考功率— Average power of reference constellation1（默认）|positive scalar

依赖性

Reference phase offset (rad)— Phase offset of reference constellation标量

依赖性

Legend— Option to display legendbutton

Trajectory— Option to display signal trajectorybutton

Measurements

Channel- 主动输入通道name of first channel in first port (default) | list of channels

Measurement Interval— Duration of EVM and MER measurement当前显示（默认）|所有显示| positive integer

EVM归一化— Normalization methodAverage constellation power（默认）|Peak constellation power

Reference Constellation— Reference constellation configurationbutton

EVM/MER— Option to display signal quality measurements panebutton

模型示例

View Constellation Diagram

View Multi-Input Constellation Diagram

Add RF Impairments to DQPSK Signal

Block Characteristics

More About

EVM和MERMeasurements

可编程配置

Extended Capabilities

C/C++ Code GenerationGenerate C and C++ code using Simulink® Coder™.

HDL Code GenerationGenerate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.

Version History

See Also

Blocks

Objects

Functions

Topics

`in_1，...，in_n`- 信号（作为单独的端口）
column vectors | matrices

`Settings`— Constellation diagram settings
button

`Number of input ports`- 示波器块上的输入端口数
`1`（默认）|integer in the range [1, 20]

`每个符号样本`— Number of samples used to represent each symbol
`1`（默认）|正整数

`Offset`— Number of samples to skip before plotting points
`0`（默认）|不nnegative integer

`Symbols to display`- 显示的最大符号数量
`Input frame length`（默认）|正整数

`Reference Constellation`— Reference constellation configuration
button

`显示参考星座`— Option to display reference constellations
`上`（默认）|`off`

`Input`— Select input port
1 (default) | positive integer

`Reference constellation`— Reference constellation
`Custom`（默认）|`BPSK`|`8-PSK`|`16 Qam`|`64-QAM`|`256-QAM`

`自定义值`— Input reference constellation
`[0.7071+0.7071I -0.7071+0.7071I -0.7071-0.7071I 0.7070-0.7071I]`（默认）|vector

`Constellation normalization`— Normalization method
`平均功率`（默认）|`Minimum distance`|`峰值功率`

`平均参考功率`— Average power of reference constellation
`1`（默认）|positive scalar

`Reference phase offset (rad)`— Phase offset of reference constellation
标量

`Legend`— Option to display legend
button

`Trajectory`— Option to display signal trajectory
button

`Channel`- 主动输入通道
name of first channel in first port (default) | list of channels

`Measurement Interval`— Duration of EVM and MER measurement
`当前显示`（默认）|`所有显示`| positive integer

`EVM归一化`— Normalization method
`Average constellation power`（默认）|`Peak constellation power`

`Reference Constellation`— Reference constellation configuration
button

`EVM/MER`— Option to display signal quality measurements pane
button

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

HDL Code Generation
Generate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.