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phased.Transmitter

Description

The Transmitter object implements a waveform transmitter.

To compute the transmitted signal:

  1. Define and set up your waveform transmitter. See Construction.

  2. Call step to compute the transmitted signal according to the properties of phased.Transmitter. The behavior of step is specific to each object in the toolbox.

Note

Starting in R2016b, instead of using the step method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.

Construction

H = phased.Transmitter creates a transmitter System object, H. This object transmits the input waveform samples with specified peak power.

H = phased.Transmitter(Name,Value) creates a transmitter object, H, with each specified property Name set to the specified Value. You can specify additional name-value pair arguments in any order as (Name1,Value1,...,NameN,ValueN).

Properties

PeakPower

Peak power

Specify the transmit peak power (in watts) as a positive scalar.

Default: 5000

Gain

Transmit gain

Specify the transmit gain (in decibels) as a real scalar.

Default: 20

LossFactor

Loss factor

Specify the transmit loss factor (in decibels) as a nonnegative scalar.

Default: 0

InUseOutputPort

Enable transmitter status output

To obtain the transmitter in-use status for each output sample, set this property to true and use the corresponding output argument when invoking step. In this case, 1's indicate the transmitter is on, and 0's indicate the transmitter is off. If you do not want to obtain the transmitter in-use status, set this property to false.

Default: false

CoherentOnTransmit

Preserve coherence among pulses

Specify whether to preserve coherence among transmitted pulses. When you set this property to true, the transmitter does not introduce any random phase to the output pulses. When you set this property to false, the transmitter adds a random phase noise to each transmitted pulse. The random phase noise is introduced by multiplication of the pulse by ewhere ϕ is a uniform random variable on the interval [0,2π].

Default: true

PhaseNoiseOutputPort

Enable pulse phase noise output

To obtain the introduced transmitter random phase noise for each output sample, set this property to true and use the corresponding output argument when invoking step. You can use in the receiver to simulate coherent on receive systems. If you do not want to obtain the random phase noise, set this property to false. This property applies when you set the CoherentOnTransmit property to false.

Default: false

SeedSource

Source of seed for random number generator

'Auto'The default MATLAB® random number generator produces the random numbers. Use 'Auto' if you are using this object with Parallel Computing Toolbox™ software.
'Property'The object uses its own private random number generator to produce random numbers. The Seed property of this object specifies the seed of the random number generator. Use 'Property' if you want repeatable results and are not using this object with Parallel Computing Toolbox software.

This property applies when you set the CoherentOnTransmit property to false.

Default: 'Auto'

Seed

Seed for random number generator

Specify the seed for the random number generator as a scalar integer between 0 and 232–1. This property applies when you set the CoherentOnTransmit property to false and the SeedSource property to 'Property'.

Default: 0

Methods

resetReset states of transmitter object
stepTransmit pulses
Common to All System Objects
release

Allow System object property value changes

Examples

collapse all

Transmit a pulse containing a linear FM waveform with a bandwidth of 5 MHz. The sample rate is 10 MHz and the pulse repetition frequency is 10 kHz.

fs = 1e7;
waveform = phased.LinearFMWaveform('SampleRate',fs, ...
    'PulseWidth',1e-5,'SweepBandwidth',5e6);
x = waveform();
transmitter = phased.Transmitter('PeakPower',5e3);
y = transmitter(x);

References

[1] Edde, B. Radar: Principles, Technology, Applications. Englewood Cliffs, NJ: Prentice Hall, 1993.

[2] Richards, M. A. Fundamentals of Radar Signal Processing. New York: McGraw-Hill, 2005.

[3] Skolnik, M. Introduction to Radar Systems, 3rd Ed. New York: McGraw-Hill, 2001.

Extended Capabilities

Version History

Introduced in R2011a