User manual MATLAB RF TOOLBOX 2

[. . . ] RF ToolboxTM 2 User's Guide How to Contact The MathWorks Web Newsgroup www. mathworks. com/contact_TS. html Technical Support www. mathworks. com comp. soft-sys. matlab suggest@mathworks. com bugs@mathworks. com doc@mathworks. com service@mathworks. com info@mathworks. com Product enhancement suggestions Bug reports Documentation error reports Order status, license renewals, passcodes Sales, pricing, and general information 508-647-7000 (Phone) 508-647-7001 (Fax) The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 For contact information about worldwide offices, see the MathWorks Web site. RF ToolboxTM User's Guide © COPYRIGHT 2004­2010 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. [. . . ] The ABCD-parameters for the shunt stub are calculated as: A =1 B=0 C = 1 / Zin D =1 When you set the StubMode property to 'Series', the 2-port network consists of a series transmission line that you can terminate with either a short circuit or an open circuit as shown in the following figure. 7-281 rfckt. parallelplate. AnalyzedResult property Zin is the input impedance of the series circuit. The ABCD-parameters for the series stub are calculated as: A =1 B = Zin C=0 D =1 The analyze method uses the S-parameters to calculate the group delay values at the frequencies specified in the analyze input argument freq, as described in the analyze reference page. Examples tx1 = rfckt. parallelplate; analyze(tx1, [1e9, 2e9, 3e9]); tx1. AnalyzedResult ans = Name: 'Data object' Freq: [3x1 double] S_Parameters: [2x2x3 double] GroupDelay: [3x1 double] NF: [3x1 double] OIP3: [3x1 double] Z0: 50 ZS: 50 ZL: 50 IntpType: 'Linear' 7-282 rfckt. parallelplate. EpsilonR property Purpose Values Description Examples Relative permittivity of dielectric Scalar The ratio of the permittivity of the dielectric, , to the permittivity of free space, 0. The default value is 2. 3. tx1=rfckt. parallelplate; tx1. EpsilonR=2. 7; 7-283 rfckt. parallelplate. LineLength property Purpose Values Description Examples Parallel-plate line length Scalar The physical length of the parallel-plate transmission line in meters. The default is 0. 01. tx1 = rfckt. parallelplate; tx1. LineLength = 0. 001; 7-284 rfckt. parallelplate. LossTangent property Purpose Values Description Examples Tangent of loss angle Scalar The loss angle tangent of the dielectric. The default is 0. tx1=rfckt. parallelplate; tx1. LossTangent=0. 002; 7-285 rfckt. parallelplate. MuR property Purpose Values Description Examples Relative permeability of dielectric Scalar The ratio of the permeability of the dielectric, , to the permeability of free space, 0. Change the relative permeability of the dielectric: tx1=rfckt. parallelplate; tx1. MuR=0. 8; 7-286 rfckt. parallelplate. Name property Purpose Values Description Examples Object name 'Parallel-Plate Transmission Line' Read-only string that contains the name of the object. tx1 = rfckt. parallelplate; tx1. Name ans = Parallel-Plate Transmission Line 7-287 rfckt. parallelplate. Separation property Purpose Values Description Examples Distance between plates Scalar Thickness, in meters, of the dielectric separating the plates. The default is 1. 0e-3. . tx1=rfckt. parallelplate; tx1. Separation=0. 8e-3; 7-288 rfckt. parallelplate. SigmaCond property Purpose Values Description Examples Conductor conductivity Scalar Conductivity, in Siemens per meter (S/m), of the conductor. The default is Inf. tx1=rfckt. parallelplate; tx1. SigmaCond=5. 81e7; 7-289 rfckt. parallelplate. StubMode property Purpose Values Description Examples Type of stub 'NotAStub' (default), 'Series', or 'Shunt' String that specifies what type of stub, if any, to include in the transmission line model. tx1 = rfckt. parallelplate; tx1. StubMode = 'Series'; 7-290 rfckt. parallelplate. Termination property Purpose Values Description Stub transmission line termination 'NotApplicable' (default), 'Open', or 'Short'. String that specifies what type of termination to use for 'Shunt'and 'Series' stub modes. Termination is ignored if the line has no stub. Use 'NotApplicable' when StubMode is 'NotAStub'. tx1 = rfckt. parallelplate; tx1. StubMode = 'Series'; tx1. Termination = 'Short'; Examples 7-291 rfckt. parallelplate. Width property Purpose Values Description Examples Transmission line width Scalar Physical width, in meters, of the parallel-plate transmission line. The default is . 005. . tx1=rfckt. parallelplate; tx1. Width=0. 001; 7-292 rfckt. parallelplate. nPort property Purpose Values Description Examples Number of ports 2 A read-only integer that indicates the object has two ports. tx1 = rfckt. parallelplate; tx1. nPort ans = 2 7-293 rfckt. passive. AnalyzedResult property Purpose Values Description Computed S-parameters, noise figure, OIP3, and group delay values rfdata. data object Handle to an rfdata. data object that contains the S-parameters, noise figure, OIP3, and group delay values computed over the specified frequency range using the analyze method. The default is a 1-by-1 rfdata. data object that contains the S-parameters, noise figure, OIP3, and group delay values that result from analyzing the values stored in the passive. s2p file at the frequencies stored in this file. The analyze method computes the AnalyzedResult property as follows: The analyze method uses the data stored in the 'NetworkData' property of the rfckt. passive object to calculate the S-parameter values of the passive component at the frequencies specified in freq. If the 'NetworkData' property contains network Y- or Z-parameters, the analyze method first converts the parameters to S-parameters. Using the interpolation method you specify with the 'IntpType' property, the analyze method interpolates the S-parameter values to determine their values at the specified frequencies. Specifically, the analyze method orders the S-parameters according to the ascending order of their frequencies, fn. It then interpolates the S-parameters, using the MATLAB interp1 function. For example, the curve in the following diagram illustrates the result of interpolating the S11 parameters at five different frequencies. 7-294 rfckt. passive. AnalyzedResult property Interpolated S11 parameter values Original S11 parameter values f1 (fmin) f2 f4 f5 f3 (fmax) Frequencies in ascending order of magnitude For more information, see "One-Dimensional Interpolation" and the interp1 reference page in the MATLAB documentation. As shown in the preceding diagram, the analyze method uses the parameter values at fmin, the minimum input frequency, for all frequencies smaller than fmin. It uses the parameters values at fmax, the maximum input frequency, for all frequencies greater than fmax. In both cases, the results may not be accurate, so you need to specify network parameter values over a range of frequencies that is wide enough to account for the component behavior. The analyze method uses the S-parameters to calculate the group delay values at the frequencies specified in the analyze input argument freq, as described in the analyze reference page. Examples pas = rfckt. passive; pas. AnalyzedResult ans = Name: 'Data object' Freq: [202x1 double] S_Parameters: [2x2x202 double] GroupDelay: [202x1 double] NF: [202x1 double] OIP3: [202x1 double] 7-295 rfckt. passive. AnalyzedResult property Z0: 50 ZS: 50 ZL: 50 IntpType: 'Linear' 7-296 rfckt. passive. IntpType property Purpose Values Description Interpolation method 'Linear' (default), 'Spline', or 'Cubic' The analyze method is flexible in that it does not require the frequencies of the specified S-parameters to match the requested analysis frequencies. [. . . ] If all phases are zero or omitted, the toolbox assumes that the small signal phase from the network parameter section of the file (180*angle(S21(f))/pi) is the phase for all power levels. In contrast, if one or more phases in the power data section are nonzero, the toolbox interpolates and extrapolates the data to determine the phase at all power levels. The small signal phase (180*angle(S21(f))/pi) from the network parameter section is ignored. A-11 A AMP File Format Inconsistency between the power data and network parameter sections of the file may cause incorrect results. To avoid this outcome, verify that the following criteria must is met: · The lowest input power value for which power data exists falls in the small signal (linear) region. [. . . ]