Main Content

Pluto Transmitter

Transmit data to Analog Devices ADALM-PLUTO radio

expand all in page

Add-On Required: This feature requires the Communications Toolbox Support Package for Analog Devices ADALM-Pluto Radio add-on.

  • Pluto Transmitter block

Libraries:
Communications Toolbox Support Package for ADALM-PLUTO Radio

Description

The Pluto Transmitter block is a signal source that sends data to an Analog Devices® ADALM-PLUTO radio. This connection enables you to simulate and develop various SDR applications.

The following diagram shows the interaction between Simulink®, the Pluto Transmitter block, and the radio hardware.

For transmitting a radio signal over the air, pass the signal generated in Simulink to an PlutoSDR transmitter block. The transmitter block forwards the signal to the radio hardware. For receiving a radio signal over the air, use an PlutoSDR receiver block. The receiver block forwards the signal received from the radio hardware for post processing in Simulink.

If the host is not connected to radio hardware, you can still use this block to develop a model that propagates sample time and data type information. To propagate this information, update your diagram.

Channel Input

The ADALM-PLUTO radio has a single channel for transmitting data from the Pluto Transmitter block. The block accepts a column vector signal of fixed length.

When the Pluto Transmitter block is called during simulation, it is possible that the host did not send valid data to the radio hardware. To determine when valid data is present, use the underflow port.

Design Custom Filter

If the gain or bandwidth characteristics of the default filter does not satisfy the requirements for your application, use the ADI filter wizard to design a custom filter that meets your specific requirements.

By using the ADI filter wizard, you can change the default filter design applied to the filter chain in the Pluto Transmitter block. To open the filter wizard, on the Advanced tab of the block, click Design custom filter. The wizard enables you to design a custom filter for the Analog Devices AD9361/AD9364 RF chip based on the Baseband sample rate (Hz) parameter. You can adjust and optimize the settings for calculating the analog filters, the interpolation and decimation filters, and the FIR coefficients. When you finish with the wizard, to apply the filter settings, click Apply on the block.

The ADI filter wizard requires the following MathWorks® products:

  • MATLAB®

  • Signal Processing Toolbox™

  • DSP System Toolbox™

For instructions on operating the ADI filter wizard, visit the Analog Devices website at MATLAB Filter Design Wizard for AD9361.

For more information, see Baseband Sampling Rate and Filter Chains.

Examples

QPSK Transmitter with ADALM-PLUTO Radio in Simulink

QPSK Transmitter with ADALM-PLUTO Radio in Simulink

Implement a QPSK transmitter using the ADALM-PLUTO Radio with Simulink, continuously transmitting indexed 'Hello world' messages at a specified center frequency. The transmitted message can be demodulated using the QPSK Receiver with ADALM-PLUTO Radio model.

Frequency Correction for ADALM-PLUTO Radio in Simulink

Frequency Correction for ADALM-PLUTO Radio in Simulink

Synchronize the baseband sample rate and center frequency of two ADALM-PLUTO radios by utilizing the Frequency correction parameter of the ADALM-PLUTO radio receiver block.

Ports

Input

expand all

Data to transmit, specified as a column vector with an even number of elements from 2 to 16,777,216. The transmission data must be complex. This is enforced due to potential for corruption of the input signal by the radio hardware IQ imbalance correction when input transmission signal is real-valued. For more information, see Quadrature Tracking.

These data types are valid for transmitted data:

  • double — Double-precision floating point with values scaled to the range of [–1,1].

  • single — Single-precision floating point with values scaled to the range of [–1,1].

  • int16 — 16-bit signed integers. The range of values is [-32768,32767], but the data transmitted by the ADALM-PLUTO radio loses the four LSBs of precision.

Note

The AD936X RF chip has a 12-bit DAC. Only the 12 most significant bits of the transmitted data are used. Values of magnitude less than 0.0625 are lost.

Dependencies

To enable this port, on the Advanced tab, set Data source select to Input Port.

Data Types: double | single | int16
Complex Number Support: Yes

RF center frequency setting in Hz, specified as a scalar from 70.0e6 to 6.0e9.

Note

Analog Devices qualifies the PLUTO radio over a tuning range of 325 MHz to 3.8 GHz. This support package enables you to use the PLUTO radio outside the qualified tuning range by configuring the radio to operate using the AD9364 firmware. To extend the frequency range, at the MATLAB command prompt, enter configurePlutoRadio('AD9364').

Example: 88.9e6 tunes the transmitter to a center frequency of 88.9 MHz.

Dependencies

To enable this port, on the Main tab, set Source of center frequency to Input Port.

Data Types: double

Transmitter gain setting in dB, specified as a scalar.

Example: 10 sets the transmitter gain level to 10 dB.

Dependencies

To enable this port, on the Main tab, set Source of gain to Input Port.

Data Types: double

Output

expand all

Lost samples indicator, returned as a logical.

  • A 0 indicates that no samples were lost.

  • A 1 indicates that samples were lost.

Note

Running the block for the first time initializes the radio. Because this initialization can result in an underflow, ignore the underflow output port value of the first run.

Parameters

expand all

Main Tab

Radio Connection

Radio identifier of the radio hardware, specified as one of the following character vectors:

  • (recommended) A device-independent index, with the prefix usb:, such as 'usb:0', 'usb:1', 'usb:2', …, indicating the first, second, third, ..., attached ADALM-PLUTO radio, respectively

  • An IP address, with the prefix ip:, such as 'ip:192.168.3.2'

  • A serial number, represented by a hexadecimal string with the prefix sn:, such as'sn:100000235523730700230031090216eaeb'

When running multiple radios on the same host, the host assigns each radio a different radio ID. When identifying the radio by USB ID, the first radio is assigned usb:0, and the ID number increments by one for subsequent radios. For example,the following configurations show IDs assigned to two radios connected on the same host computer for a pair of Pluto Receiver and Pluto Transmitter blocks.

Set the radio ID for each connected radios.

When operating on Windows® keep these considerations in mind.

  • When running multiple radios on the same host in separate MATLAB sessions, for each MATLAB session the first radio is assigned usb:0, and the ID number increments by one for subsequent radios.

  • Radios that are being used by one MATLAB are not seen by other MATLAB sessions. Use findPlutoRadio and check the reported serial number to identify the radios seen in a particular MATLAB session.

For more information, see Setup for Two Radios Connecting to One Host.

Click Info to open a window that communicates with the attached radio hardware to obtain basic radio hardware information.

Note

  • The actual computed value and your specified setting can have a small mismatch. To confirm that the actual computed value is close enough to your specified setting, click Info on the block. This button synchronizes the block with the radio hardware.

  • When the Frequency correction (ppm) setting is 0, the factory-calibrated setting of the radio will be used.

  • The Frequency correction (ppm) parameter changes the actual radio setting for Baseband sample rate (Hz) and Center frequency (Hz).

Radio Properties

Source of center frequency, specified as one of the following:

Dialog

Specify the center frequency in the Center frequency (Hz) parameter.

Input Port

Specify the center frequency in Hz by using an input that is added to the block.

RF center frequency setting in Hz, specified as a scalar from 70.0e6 to 6.0e9.

Note

Analog Devices qualifies the PLUTO radio over a tuning range of 325 MHz to 3.8 GHz. This support package enables you to use the PLUTO radio outside the qualified tuning range by configuring the radio to operate using the AD9364 firmware. To extend the frequency range, at the MATLAB command prompt, enter configurePlutoRadio('AD9364').

Dependencies

To enable this parameter, set Source of center frequency to Dialog.

Source of gain, specified as one of the following:

Dialog

Specify the gain in the Gain (dB) parameter.

Input Port

Specify the gain in dB by using an input that is added to the block.

Radio transmitter gain in dB, specified as a scalar from -87.5 to 0. The resolution is 0.25 dB.

Dependencies

To enable this parameter, set Source of gain to Dialog.

This parameter is read-only.

The channel mapping is always set to 1.

Baseband sampling rate in Hz, specified as a scalar from 65105 to 61.44e6.

Note

The actual computed value and your specified setting can have a small mismatch. To confirm that the actual computed value is close enough to your specified setting, click Info on the block. This button synchronizes the block with the radio hardware.

Data

Select Enable output port for underflow indicator to add the underflow output port to the Pluto Transmitter block.

Filter Tab

When you select this parameter, the filter chain uses a custom filter design instead of the default. If Pluto Transmitter block does not have a custom filter design applied yet, click on Launch filter wizard to design and apply a new filter.

Note

When applying a custom filter to Pluto Transmitter block using the ADI filter wizard, Use custom filter is automatically selected. To switch between the default and your custom filter design, on the Filter tab of the block mask, clear or select Use custom filter, respectively.

For more information, see Baseband Sampling Rate and Filter Chains.

Advanced Tab

Data

Select source of data, specified as:

  • Input port — Source for the transmission signal is the data input port

  • DDS — Source for the transmission signal is direct digital synthesis (DDS) on the radio hardware. The transmitter has two additive tones. To set the tone frequency and tone scale of these tones, use the Tone 1 Frequency (Hz), Tone 2 Frequency (Hz), Tone 1 Scale [0-1], and Tone 2 Scale [0-1] parameters.

Frequency of the first DDS tone in Hz, specified as a scalar in the range [0, (Baseband sample rate / 2)].

Dependencies

To enable this parameter, set Data source select to DDS.

Frequency of the second DDS tone in Hz, specified as a scalar in the range is [0, (Baseband sample rate / 2)].

Dependencies

To enable this parameter, set Data source select to DDS.

Scale of the first DDS tone in millionths of full scale, specified as a scalar in the range [0,1]. The values are relative to the DAC output amplitude, where 0 is zero amplitude and 1 is 1e6, the maximum DAC output amplitude.

Dependencies

To enable this parameter, set Data source select to DDS.

Scale of the second DDS tone in millionths of full scale, specified as a scalar in the range [0,1]. The values are relative to the DAC output amplitude, where 0 is zero amplitude and 1 is 1e6, the maximum DAC output amplitude.

Dependencies

To enable this parameter, set Data source select to DDS.

Frequency correction in parts per million, specified as a scalar from -200 to 200.

Note

  • When the Frequency correction (ppm) setting is 0, the factory-calibrated setting of the radio will be used.

  • The Frequency correction (ppm) parameter changes the actual radio setting for Baseband sample rate (Hz) and Center frequency (Hz).

Built-in Self-test Configuration

Select built-in self-test loopback mode, specified as one of these options:

  • Disabled — Disable BIST loopback.

  • Digital Tx -> Digital Rx — Enable digital signals to loop back within the AD936x device. The signals bypass the RF stage.

  • RF Rx -> RF Tx — Enable incoming receiver RF signals to loop back to the RF transmitter port. The signals bypass the FPGA.

Select BIST signal injection mode, specified as one of the following values:

  • Disabled — Disable BIST signal injection.

  • Tone Inject Tx — Enable BIST signal injection to transmit path.

  • Tone Inject Rx — Enable BIST signal injection to receive path.

When you enable BIST signal injection, you can set the source of BIST signal generation with the Signal generator mode parameter.

Select source of BIST signal generation, specified as one of these options:

  • PRBS — Use the pseudo random binary sequence (PRBS) generator of the board.

  • Tone — Use the tone generator of the board. To set the tone frequency and tone level, use the Tone frequency (Hz) and Tone level (dB) parameters, respectively.

Dependencies

To enable this parameter, set Test signal injection to Tone Inject Tx or Tone Inject Rx.

Select BIST tone frequency, specified as Fs/32, Fs/16, Fs*3/32, or Fs/8.

Dependencies

To enable this parameter, set Signal generator mode to Tone.

Select BIST tone level, specified as 0, -6, -12, or -18.

Dependencies

To enable this parameter, set Signal generator mode to Tone.

Version History

Introduced in R2017a

See Also

Blocks

Functions

Objects

Topics

External Websites