%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 2007 Tektronix RTSA Demo program
%
% This program provides a simple example of VISA control of an RTSA61xx series
% spectrum analyzer through MATLAB
%
% To complete this demo you should have TEK VISA installed as well as MATLAB
% with the intrument control toolbox. The RTSA should have a simple antenna
% connected to the RF input
%
%
%
%
%
%
% October 2007 Tektronix Inc. Version 2006.10.12.c
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function RTSA6100__Plot_Spectrum
warning off all
%5 MATLAB:Polynomial is not unique
% warning off MATLAB:degree >= number of data points
warning off MATLAB:polyfit:RepeatedPointsOrRescale
clc; % Clear the command window
close % Close all open figure windows
clear
format compact
global x
global y
global PeakNumber
global P
%%
%--------------------------------------------------------------------------
% User Setup
%--------------------------------------------------------------------------
% Change the IP addresses to match the IP address of your RSA before
% running the demo.
RTSAIPAddr = '192.168.1.113'; % Instrument TCP/IP address
%
%
%--------------------------------------------------------------------------
%% Step 1: Open the VISA connection to the RSA
rtsa = visa( 'tek', ['TCPIP::' RTSAIPAddr '::INSTR'] ); % Setup VISA session with instrument
set( rtsa, 'InputBufferSize', 131072 ); % Set input buffer, should be 4x number of trace points minimum
set( rtsa, 'Timeout', 50.0 ); % Set long GPIB time-out in case of long sweeps
fopen( rtsa );
% Query the RSA for its identification and display the results.
% NOTE: This is using the MATLAB Instrument Control Toolbox version of the
% query command.
[ strIDN, numChars, errMsg ] = query( rtsa, '*IDN?' );
%% Step 2: Setup the RSA using SCPI commands
% Preset the RSA and turn off continuous mode
fprintf( rtsa, '*RST'); % Reset instrument
query ( rtsa, '*OPC?' ); % Query OPC to confirm Reset is done
fprintf( rtsa, ':INIT:CONT off' ); % Set single aquisition mode
fprintf( rtsa, ':SENS:SPEC:FREQ:STAR 88 MHz' ); % Set start frequency
fprintf( rtsa, ':SENS:SPEC:FREQ:STOP 108 MHz' ); % Set stop frequency
fprintf( rtsa, ':SENS:SPEC:BAND:RES 10kHz' ); % Set RBW
fprintf( rtsa, ':TRAC1:SPEC:FUNC AVER' ); % Setup trace averaging
fprintf( rtsa, ':TRAC1:SPEC:AVER:COUN 3' ); % Average 3 traces
fprintf( rtsa, ':INPUT:MLEVEL -30' ); % Set reference level to -30 dBm
%% Step 3: Fetch Trace & Display
tic; % Start Timer
fprintf( rtsa, ':INIT' ); %Trigger an aquisition
query( rtsa, '*OPC?'); % Query OPC to confirm operation complete
sw_time = toc; % Calculate Elapsed Time
Start_Freq = str2double(query( rtsa, ':SENS:SPEC:FREQ:STAR?' ))/1e6; % Get start frequency
Stop_Freq = str2double(query( rtsa, ':SENS:SPEC:FREQ:STOP?' ))/1e6; % Get stop frequency
fprintf( rtsa, ':FETC:SPEC:TRAC1?' ); % Fetch the trace
y = ParseBinary32Bit_SCPI( rtsa ); % Convert the trace
x_range = size(y); % Determine # of points
figure(1);clf
x=[1:1:x_range(2)]; % Create a dummy vector same size as # of trace points
plot(x,y);
ylim([ -120 0.0 ]); % Set power axis to 120 dB
xlim([ 0 x_range(2) ]); % Autoset the x axis for the graph based on # of trace points
grid on;
xlabel(['Start = ' num2str(Start_Freq) ' MHz AQT = ' num2str(sw_time) ' sec. Stop = ' num2str(Stop_Freq) ' MHz ']);
ylabel ('Amplitude (dBm)');
title(strIDN);
%% Determine the Peak in the Trace
mean_pwr = mean(y); % Calculate mean power within the span (not technically correct but works for now)
mn_pwr = mean_pwr + 6; % Add 6 dB margin
P=findpeaks(x,y,0.9,mn_pwr,1,1);
figure(1);text(P(:, 2),P(:, 3),num2str(P(:,1))) % Number the peaks found on the graph
' Peak # Position Amplitude '
P % Display table of peaks
return
%%
