GNU Radio Radar Toolbox
gr::radar::estimator_rcs Class Referenceabstract

Basic RCS block for estimating the RCS of a single target. Some hardware specs need to be known for calculating RCS values, see parameters for details. The radar equation is used to calculate the RCS: RCS = Pr*(4pi)^3*R^4/(Pt*Gt*Gr*lamda^2). The Rx power (Pr) and the distance (R) are being estimated, while the other parameters are given in the flowgraph. It is possible to average a number of samples by setting the num_mean value > 1. The RCS will be 0 until enough samples are collected to calculate the mean value (be patient). The Tx power (Pt) needs to be calibrated with external hardware. I recommend to calibrate for the wanted power and not to change the parameters in the flowgraph on the Tx side after that. The RCS block needs the Rx power, to estimate the RCS. For that, the input power of the block needs to be determined analytically and altered via the corr_factor and exponent values, to fit the following equation: Pr = P_input ^ (exponent) * corr_factor / Pt. In addition, the FFTs need to be normalized for correct power calculation. More...

#include <estimator_rcs.h>

Inheritance diagram for gr::radar::estimator_rcs:
gr::radar::estimator_rcs_impl

Public Types

typedef std::shared_ptr< estimator_rcssptr
 

Public Member Functions

virtual void set_num_mean (int val)=0
 
virtual void set_center_freq (float val)=0
 
virtual void set_antenna_gain_tx (float val)=0
 
virtual void set_antenna_gain_rx (float val)=0
 
virtual void set_usrp_gain_rx (float val)=0
 
virtual void set_power_tx (float val)=0
 
virtual void set_corr_factor (float val)=0
 

Static Public Member Functions

static sptr make (int num_mean, float center_freq, float antenna_gain_tx, float antenna_gain_rx, float usrp_gain_rx, float power_tx, float corr_factor, float exponent=1)
 Return a shared_ptr to a new instance of radar::estimator_rcs.
 

Detailed Description

Basic RCS block for estimating the RCS of a single target. Some hardware specs need to be known for calculating RCS values, see parameters for details. The radar equation is used to calculate the RCS: RCS = Pr*(4pi)^3*R^4/(Pt*Gt*Gr*lamda^2). The Rx power (Pr) and the distance (R) are being estimated, while the other parameters are given in the flowgraph. It is possible to average a number of samples by setting the num_mean value > 1. The RCS will be 0 until enough samples are collected to calculate the mean value (be patient). The Tx power (Pt) needs to be calibrated with external hardware. I recommend to calibrate for the wanted power and not to change the parameters in the flowgraph on the Tx side after that. The RCS block needs the Rx power, to estimate the RCS. For that, the input power of the block needs to be determined analytically and altered via the corr_factor and exponent values, to fit the following equation: Pr = P_input ^ (exponent) * corr_factor / Pt. In addition, the FFTs need to be normalized for correct power calculation.

Parameters
num_meanNumber of samples taken into account for calculating mean value (1 for no mean calculation)
center_freqCenter frequency of radar
antenna_gain_txAntenna Gain of the Tx antenna
antenna_gain_rxAntenna Gain of the Rx antenna
usrp_gain_rxRx gain of USRP set in flowgraph
power_txTx power of radar signal. Needs to be measured one time!
corr_factorCorrection factor for the RCS to calibrate system to a known target or special signal paths
exponentExponent of the input power to calculate Rx power, depends on signal path (calculate analytically)

Member Typedef Documentation

◆ sptr

Member Function Documentation

◆ make()

static sptr gr::radar::estimator_rcs::make ( int  num_mean,
float  center_freq,
float  antenna_gain_tx,
float  antenna_gain_rx,
float  usrp_gain_rx,
float  power_tx,
float  corr_factor,
float  exponent = 1 
)
static

Return a shared_ptr to a new instance of radar::estimator_rcs.

To avoid accidental use of raw pointers, radar::estimator_rcs's constructor is in a private implementation class. radar::estimator_rcs::make is the public interface for creating new instances.

◆ set_antenna_gain_rx()

virtual void gr::radar::estimator_rcs::set_antenna_gain_rx ( float  val)
pure virtual

◆ set_antenna_gain_tx()

virtual void gr::radar::estimator_rcs::set_antenna_gain_tx ( float  val)
pure virtual

◆ set_center_freq()

virtual void gr::radar::estimator_rcs::set_center_freq ( float  val)
pure virtual

◆ set_corr_factor()

virtual void gr::radar::estimator_rcs::set_corr_factor ( float  val)
pure virtual

◆ set_num_mean()

virtual void gr::radar::estimator_rcs::set_num_mean ( int  val)
pure virtual

◆ set_power_tx()

virtual void gr::radar::estimator_rcs::set_power_tx ( float  val)
pure virtual

◆ set_usrp_gain_rx()

virtual void gr::radar::estimator_rcs::set_usrp_gain_rx ( float  val)
pure virtual

The documentation for this class was generated from the following file: