info

Characteristic information about object

Since R2021a

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    Syntax

    s = info(obj)

    Description

    s = info(obj) returns a structure containing the characteristic information of the specified input object obj.

    example

    Examples

    collapse all

    Open Live Script

    Get information from a dvbs2WaveformGenerator System object by using the info function. Then retrieve the filter residual samples by using the flushFilter object function.

    This example uses MAT-files with LDPC parity matrices. If the MAT-files are not available on the path, download and unzip the MAT-files by entering this code at the MATLAB command prompt.

    if ~exist('dvbs2xLDPCParityMatrices.mat','file')
    if ~exist('s2xLDPCParityMatrices.zip', 'file')
        url = 'https://ssd.mathworks.com/supportfiles/spc/satcom/DVB/s2xLDPCParityMatrices.zip';
        websave('s2xLDPCParityMatrices.zip',url);
        unzip('s2xLDPCParityMatrices.zip');
    end
addpath('s2xLDPCParityMatrices');
end

    Specify the number of physical layer (PL) frames per stream.

    numFrames = 1;

    Create a Digital Video Broadcasting standard (DVB-S2) System object, and then specify its properties.

    s2WaveGen = dvbs2WaveformGenerator;
s2WaveGen.NumInputStreams = 2;
s2WaveGen.MODCOD = [21 16];
s2WaveGen.DFL   = 47008;
s2WaveGen.ISSYI = true;
s2WaveGen.SamplesPerSymbol = 2;
disp(s2WaveGen)
      dvbs2WaveformGenerator with properties:

           StreamFormat: "TS"
        NumInputStreams: 2
               FECFrame: "normal"
                 MODCOD: [21 16]
                    DFL: 47008
          ScalingMethod: "outer radius as 1"
              HasPilots: 0
          RolloffFactor: 0.3500
    FilterSpanInSymbols: 10
       SamplesPerSymbol: 2
                  ISSYI: true
             ISCRFormat: "short"

  Show all properties

    Get the characteristic information about the DVB-S2 waveform generator.

    info(s2WaveGen)
    ans = struct with fields:
      ModulationScheme: {'16APSK'  '8PSK'}
    LDPCCodeIdentifier: {'5/6'  '8/9'}

    Create the bit vector of input information bits, data, of concatenated TS user packets.

    syncBits = [0 1 0 0 0 1 1 1]';       % Sync byte for TS packet is 47 Hex
pktLen = 1496;                       % UP length without sync bits is 1496
data =  cell(1,s2WaveGen.NumInputStreams);
for i = 1:s2WaveGen.NumInputStreams
    numPkts = s2WaveGen.MinNumPackets(i)*numFrames;
    txRawPkts = randi([0 1],pktLen,numPkts);
    ISSY = randi([0 1],16,numPkts);   % ISCRFormat is 'short' by default
                                      % 'short' implies the default length of ISSY as 2 bytes
    txPkts = [repmat(syncBits,1,numPkts);txRawPkts;ISSY];    % ISSY is appended at the end of UP
    data{i} = txPkts(:);
end

    Generate a DVB-S2 time-domain waveform using the information bits.

    txWaveform = [s2WaveGen(data)];

    Check the filter residual data samples that remain in the filter delay.

    flushFilter(s2WaveGen)
    ans = 20×1 complex

   0.0153 + 0.4565i
   0.2483 + 0.5535i
   0.3527 + 0.3972i
   0.3541 - 0.0855i
   0.3505 - 0.4071i
   0.4182 - 0.1962i
   0.5068 + 0.0636i
   0.4856 - 0.1532i
   0.3523 - 0.4153i
   0.1597 - 0.2263i
      ⋮
    Open Live Script

    Get information from a dvbs2xWaveformGenerator System object by using the info function. Then retrieve the filter residual samples by using the flushFilter object function.

    This example uses MAT-files with LDPC parity matrices. If the MAT-files are not available on the path, download and unzip the MAT-files by entering this code at the MATLAB command prompt.

    if ~exist('dvbs2xLDPCParityMatrices.mat','file')
    if ~exist('s2xLDPCParityMatrices.zip','file')
        url = 'https://ssd.mathworks.com/supportfiles/spc/satcom/DVB/s2xLDPCParityMatrices.zip';
        websave('s2xLDPCParityMatrices.zip',url);
        unzip('s2xLDPCParityMatrices.zip');
    end
addpath('s2xLDPCParityMatrices');
end

    Specify the number of physical layer (PL) frames per stream.

    numFrames = 2;

    Create a Digital Video Broadcasting Satellite Second Generation extended (DVB-S2X) System object and specify its properties. Use time slicing technique and variable coding and modulation configuration mode.

    s2xWaveGen = dvbs2xWaveformGenerator();
s2xWaveGen.HasTimeSlicing = true;
s2xWaveGen.NumInputStreams = 2;
s2xWaveGen.PLSDecimalCode = [135 145];   % QPSK 9/20 and 8PSK 25/36
s2xWaveGen.DFL = [18048 44656];
s2xWaveGen.PLScramblingIndex = [0 1];
disp(s2xWaveGen)
      dvbs2xWaveformGenerator with properties:

           StreamFormat: "TS"
         HasTimeSlicing: true
        NumInputStreams: 2
         PLSDecimalCode: [135 145]
                    DFL: [18048 44656]
      PLScramblingIndex: [0 1]
          RolloffFactor: 0.3500
    FilterSpanInSymbols: 10
       SamplesPerSymbol: 4
                  ISSYI: false

  Show all properties

    Get the characteristic information about the DVB-S2X waveform generator.

    info(s2xWaveGen)
    ans = struct with fields:
              FECFrame: {'normal'  'normal'}
      ModulationScheme: {'QPSK'  '8PSK'}
    LDPCCodeIdentifier: {'9/20'  '25/36'}

    Create the bit vector of input information bits, data, of concatenated TS user packets for each input stream.

    syncBits = [0 1 0 0 0 1 1 1]';       % Sync byte for TS packet is 47 Hex
pktLen = 1496;                       % UP length without sync bits is 1496
data =  cell(1, s2xWaveGen.NumInputStreams);
for i = 1:s2xWaveGen.NumInputStreams
    numPkts = s2xWaveGen.MinNumPackets(i)*numFrames;
    txRawPkts = randi([0 1], pktLen, numPkts);
    txPkts = [repmat(syncBits, 1, numPkts); txRawPkts];
    data{i} = txPkts(:);
end

    Generate a DVB-S2X time-domain waveform using the information bits.

    txWaveform = s2xWaveGen(data);

    Check the filter residual data samples that remain in the filter delay.

    flushFilter(s2xWaveGen)
    ans = 40×1 complex

  -0.2412 - 0.0143i
  -0.2619 - 0.0861i
  -0.2726 - 0.1337i
  -0.2511 - 0.1597i
  -0.1851 - 0.1680i
  -0.0780 - 0.1602i
   0.0448 - 0.1288i
   0.1598 - 0.0751i
   0.2482 - 0.0049i
   0.3026 + 0.0702i
      ⋮
    Open Live Script

    Get information from a dvbrcs2WaveformGenerator System object by using the info object function.

    Create a DVB-RCS2 System object, and then specify its properties.

    wg = dvbrcs2WaveformGenerator;
wg.ContentType = "control";
wg.WaveformID = 33;
wg.FilterSpanInSymbols = 12;
disp(wg)
      dvbrcs2WaveformGenerator with properties:

      TransmissionFormat: "TC-LM"
             ContentType: "control"
        IsCustomWaveform: false
              WaveformID: 33
     PreBurstGuardLength: 0
    PostBurstGuardLength: 0
     FilterSpanInSymbols: 12
        SamplesPerSymbol: 4

   Read-only:
          FramePDULength: 784

    Get the characteristic information about the DVB-RCS2 waveform generator.

    info(wg)
    ans = struct with fields:
              BurstLength: 566
     PayloadLengthInBytes: 100
            MappingScheme: "QPSK"
                 CodeRate: "3/4"
           PreambleLength: 32
          PostambleLength: 0
              PilotPeriod: 0
         PilotBlockLength: 0
    PermutationParameters: [23 10 8 2 1]
               UniqueWord: "0C330C0FF3F3033F"
                 PilotSum: 0
    Open Live Script

    Get information from a ccsdsTMWaveformGenerator System object by using the info function. Then retrieve the filter residual samples by using the flushFilter object function.

    Create a Consultative Committee for Space Data Systems (CCSDS) Telemetry (TM) System object. Set the waveform type as synchronization and channel coding with low-density parity-check (LDPC) channel coding. Display the properties.

    tmWaveGen = ccsdsTMWaveformGenerator;
tmWaveGen.WaveformSource = "synchronization and channel coding";
tmWaveGen.ChannelCoding = "LDPC";
tmWaveGen.NumBitsInInformationBlock = 1024;
tmWaveGen.Modulation = "QPSK";
tmWaveGen.CodeRate = "1/2";
disp(tmWaveGen)
      ccsdsTMWaveformGenerator with properties:

               WaveformSource: "synchronization and channel coding"
                HasRandomizer: true
                       HasASM: true
                    PCMFormat: "NRZ-L"

   Channel coding
                ChannelCoding: "LDPC"
    NumBitsInInformationBlock: 1024
                     CodeRate: "1/2"
                 IsLDPCOnSMTF: false

   Digital modulation and filter
                   Modulation: "QPSK"
           PulseShapingFilter: "root raised cosine"
                RolloffFactor: 0.3500
          FilterSpanInSymbols: 10
             SamplesPerSymbol: 10

  Show all properties

    Specify the number of transfer frames.

    numTF = 20;

    Get the characteristic information about the CCSDS TM waveform generator.

    info(tmWaveGen)
    ans = struct with fields:
         ActualCodeRate: 0.5000
       NumBitsPerSymbol: 2
    SubcarrierFrequency: []

    Generate the input bits for the CCSDS TM waveform generator, and then generate the waveform.

    bits = randi([0 1], tmWaveGen.NumInputBits*numTF,1);
waveform = tmWaveGen(bits);

    Check the filter residual data samples that remain in the filter delay.

    flushFilter(tmWaveGen)
    ans = 100×1 complex

  -0.0772 - 0.0867i
  -0.0751 - 0.0859i
  -0.0673 - 0.0788i
  -0.0549 - 0.0654i
  -0.0388 - 0.0469i
  -0.0200 - 0.0250i
   0.0002 - 0.0012i
   0.0208 + 0.0227i
   0.0405 + 0.0453i
   0.0587 + 0.0653i
   0.0745 + 0.0818i
   0.0870 + 0.0936i
   0.0972 + 0.1019i
   0.1045 + 0.1064i
   0.1090 + 0.1075i
      ⋮
    Open Live Script

    Get information from a etsiRicianChannel System object by using the info object function.

    Create a European Telecommunication Standards Institute (ETSI) Rician channel System object, and then specify its properties.

    chan = etsiRicianChannel;
chan.SampleRate = 2e5;     
chan.KFactor = 10;
chan.MaximumDopplerShift = 20;
chan.NumSinusoids = 58;
disp(chan)
      etsiRicianChannel with properties:

             SampleRate: 200000
                KFactor: 10
    MaximumDopplerShift: 20

  Show all properties

    Pass data through the channel.

    txWaveform = randi([0 1],500,1);
rxWaveform = chan(txWaveform);

    Get the characteristic information about the ETSI Rician channel.

    info(chan)
    ans = struct with fields:
           ChannelFilterDelay: 0
    ChannelFilterCoefficients: 1
          NumSamplesProcessed: 500
    Open Live Script

    Get channel information from a p681LMSChannel System object by using the info object function.

    Create an ITU-R P.681-11 LMS channel System object and specify its properties.

    chan = p681LMSChannel;
chan.SampleRate = 10e3;             % Hz
chan.MobileSpeed = 2;               % m/s
chan.Environment = "RuralWooded";
disp(chan)
      p681LMSChannel with properties:

                NumStates: 2
               SampleRate: 10000
             InitialState: "Good"
         CarrierFrequency: 2.2000e+09
           ElevationAngle: 45
              MobileSpeed: 2
       AzimuthOrientation: 0
    SatelliteDopplerShift: 0
              Environment: "RuralWooded"
         ChannelFiltering: true

  Show all properties

    QPSK-modulate a random input signal, and then pass it through the channel.

    numSamples = 2e4;
txWaveform = pskmod(randi([0 3],numSamples,1),4);
[rxWaveform,pathGains,sampleTimes,stateSeries] = chan(txWaveform);

    Get the characteristic information about the P.681-11 LMS channel.

    info(chan)
    ans = struct with fields:
                   PathDelays: 0
           ChannelFilterDelay: 0
    ChannelFilterCoefficients: 1
          NumSamplesProcessed: 20000

    Transmit another QPSK-modulated random input signal through the channel

    numSamples2 = 3e4;
txWaveform2 = pskmod(randi([0 3],numSamples2,1),4);
[rxWaveform2,pathGains2,sampleTimes2,stateSeries2] = chan(txWaveform2);

    Observe the change in number of samples processed.

    info(chan)
    ans = struct with fields:
                   PathDelays: 0
           ChannelFilterDelay: 0
    ChannelFilterCoefficients: 1
          NumSamplesProcessed: 50000
    Open Live Script

    Get channel information from a LutzLMSChannel System object by using the info object function.

    Create a Lutz LMS channel System object and specify its properties.

    chan = lutzLMSChannel;
chan.SampleRate = 6000;
chan.KFactor = 20;
chan.MeanStateDuration = [8 2];
disp(chan)
      lutzLMSChannel with properties:

                   SampleRate: 6000
                 InitialState: "Good"
                      KFactor: 20
              LogNormalFading: [-8.8000 3.8000]
    StateDurationDistribution: "Exponential"
            MeanStateDuration: [8 2]
          MaximumDopplerShift: 4.2807
             ChannelFiltering: true

  Show all properties

    QPSK-modulate a random input signal, and then pass it through the channel.

    numSamples = 2e4;
txWaveform = pskmod(randi([0 3],numSamples,1),4);
[rxWaveform,pathGains,sampleTimes,stateSeries] = chan(txWaveform);

    Get the characteristic information about the Lutz LMS channel.

    info(chan)
    ans = struct with fields:
                   PathDelays: 0
           ChannelFilterDelay: 0
    ChannelFilterCoefficients: 1
          NumSamplesProcessed: 20000

    Transmit another QPSK-modulated random input signal through the channel

    numSamples2 = 3e4;
txWaveform2 = pskmod(randi([0 3],numSamples2,1),4);
[rxWaveform2,pathGains2,sampleTimes2,stateSeries2] = chan(txWaveform2);

    Observe the change in number of samples processed.

    info(chan)
    ans = struct with fields:
                   PathDelays: 0
           ChannelFilterDelay: 0
    ChannelFilterCoefficients: 1
          NumSamplesProcessed: 50000
    Open Live Script

    Get information from a gpsPCode System object™ by using the info object function. Observe how the precision of initial time impacts the generation of the P-code.

    Create a P-code generator System object™, and then specify its properties.

    format long
pgen = gpsPCode
    pgen = 
  gpsPCode with properties:

                 PRNID: 1
      OutputCodeLength: 10230
    InitialStateFormat: "seconds"
           InitialTime: 0


    pgen.InitialStateFormat = "chips";
pgen.InitialNumChipsElapsed = 8388600;

    Get the characteristic information about the P-code generator.

    pgen.info
    ans = struct with fields:
    TotalNumChipsElapsed: 8388600
     TotalSecondsElapsed: 0.820000000000000

    Advance the time by a quarter of a P-code chip time (that is, 0.25/10.23e6).

    pgen1 = gpsPCode;
pgen1.InitialTime = pgen.info.TotalSecondsElapsed + 0.25/10.23e6
    pgen1 = 
  gpsPCode with properties:

                 PRNID: 1
      OutputCodeLength: 10230
    InitialStateFormat: "seconds"
           InitialTime: 0.820000024437928


    pgen1.info
    ans = struct with fields:
    TotalNumChipsElapsed: 8388600
     TotalSecondsElapsed: 0.820000000000000

    The info function output shows no increment in the TotalNumChipsElapsed in this case, because TotalNumChipsElapsed is calculated internally using the function round.

    Advance the time by half of a P-code chip time now (that is, 0.5/10.23e6).

    pgen2 = gpsPCode;
pgen2.InitialTime = pgen.info.TotalSecondsElapsed + 0.5/10.23e6
    pgen2 = 
  gpsPCode with properties:

                 PRNID: 1
      OutputCodeLength: 10230
    InitialStateFormat: "seconds"
           InitialTime: 0.820000048875855


    pgen2.info
    ans = struct with fields:
    TotalNumChipsElapsed: 8388601
     TotalSecondsElapsed: 0.820000097751711

    The info function output now shows the TotalNumChipsElapsed is incremented by one, due to the internal usage of round() function.

    Compare the output of each System object call.

    code = pgen();
code1 = pgen1();
code2 = pgen2();
isequal(code, code1) % code and code1 are equal
    ans = logical
   1


    isequal(code1,code2) % code1 and code2 are unequal
    ans = logical
   0
    Open Live Script

    Get channel information from a gnssSignalAquirer System object by using the info object function.

    Load a precomputed GPS waveform.

    load gnssWaveforms

    Initialize a GNNS signal Acquirer system object.

    gsa = gnssSignalAcquirer(IntermediateFrequency=10e6,SampleRate=38.192e6);

    Search for 32 GPS satellites.

    Information = gsa(gpsIFWaveform,1:32); % Information about frequency Offset, code-phase Offset, and detection of a satellite for each PRN ID

    Get the characteristic information about the GNSS signal acquisition .

    gsaInfo = info(gsa)
    gsaInfo = struct with fields:
    ReferenceNoiseLevel: 1.2586e+03

    Input Arguments

    collapse all

    Output Arguments

    collapse all

    Characteristic information of the specified object, returned as a structure. The fields of the structure depend on the obj input.

    • If obj is a dvbs2WaveformGenerator System object, the output structure has these fields, consisting of physical layer information about the Digital Video Broadcasting Satellite Second Generation (DVB-S2) waveform generator.

      FieldValueDescription
      ModulationSchemeString scalar (default) or cell array of character vectorsModulation scheme, returned as a string scalar for single-input stream and a cell array of character vectors of length equal to the NumInputStreams property of the dvbs2WaveformGenerator object for multi-input streams.
      LDPCCodeIdentifierString scalar (default) or cell array of character vectorsLDPC code identifier used in forward error correction (FEC), returned as a string scalar for single-input stream and a cell array of character vectors of length equal to NumInputStreams property of the dvbs2WaveformGenerator object for multi-input streams.

    • If obj is a dvbs2xWaveformGenerator System object, the output structure has these fields, consisting of physical layer information about the Digital Video Broadcasting Satellite Second Generation extended (DVB-S2X) waveform generator.

      FieldValueDescription
      FECFrameString scalar (default) or cell array of character vectorsFEC frame format, returned as a string scalar for single-input stream and a cell array of character vectors of length equal to NumInputStreams property of dvbs2xWaveformGenerator object for multi-input streams.
      ModulationSchemeString scalar (default) or cell array of character vectorsModulation scheme, returned as a string scalar for single-input stream and a cell array of character vectors of length equal to NumInputStreams property of dvbs2xWaveformGenerator object for multi-input streams.
      LDPCCodeIdentifierString scalar (default) or cell array of character vectorsLDPC code identifier used in forward error correction (FEC), returned as a string scalar for single-input stream and a cell array of character vectors of length equal to NumInputStreams property of dvbs2xWaveformGenerator object for multi-input streams.

    • If obj is a dvbrcs2WaveformGenerator System object, the output structure has these fields, consisting of physical layer information about the Digital Video Broadcasting Second Generation Return Channel over Satellite (DVB-RCS2) waveform generator.

      FieldValueDescription
      BurstLengthpositive integer

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — Length of the burst, in symbols, prior to the pulse shaping, returned as a positive integer.

      When you set the TransmissionFormat property of the object to "CC-CPM" — Length of the burst, in symbols, returned as a positive integer.

      PayloadLengthInBytesinteger in the range [3, 65535]

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — Input data length, in bytes, to the forward error correction (FEC) encoder, returned as an integer in the range [3, 65535].

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      FECInputLengthpositive integer

      When you set the TransmissionFormat property of the object to "CC-CPM" — Length of the input bit sequence to the channel encoder, returned as a positive integer.

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — This field is not applicable.

      MappingScheme"pi/2-BPSK", "QPSK", "8PSK", or "16QAM"

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — Symbol mapping and modulation scheme to use to generate the DVB-RCS2 waveform, returned as "pi/2-BPSK", "QPSK", "8PSK", or "16QAM".

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      CodeRate"1/3", "1/2", "2/3", "3/4", "4/5", "5/6", "6/7", or "7/8"

      Code rate of the channel encoder, returned as "1/3", "1/2", "2/3", "3/4", "4/5", "5/6", "6/7", or "7/8".

      PreambleLengthinteger in the range [0, 255]

      Number of preamble symbols prefixed to the burst symbols prior to the modulation, returned as an integer in the range [0, 255].

      • When you set the TransmissionFormat property of the object to "TC-LM" — The unit of preamble length is symbols.

      • When you set the TransmissionFormat property of the object to "SS-TC-LM" — The unit of preamble length is chips.

      • When you set the TransmissionFormat property of the object to "CC-CPM" — The unit of preamble length is bits.

        For CC-CPM waveforms, the premable length is set to 64 bits.

      MidambleLengthinteger in the range [0, 255]

      The number of midamble bits inserted in the CC-CPM burst, returned as an integer in the range [0, 255].

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      For CC-CPM waveforms, the midamble length is set to 64 bits.

      PostambleLengthinteger in the range [0, 255]

      Number of postamble symbols suffixed to the burst symbols prior to the modulation, returned as an integer in the range [0, 255].

      • When you set the TransmissionFormat property of the object to "TC-LM" — The unit of preamble length is symbols.

      • When you set the TransmissionFormat property of the object to "SS-TC-LM" — The unit of preamble length is chips.

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      PilotPeriodinteger in the range [0, 4095]

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — Pilot symbol periodicity, including the burst symbols, returned as an integer in the range [0, 4095].

      This period represents the length of the sequence from the first symbol of a pilot block to the first symbol of the next pilot block in symbols or chips.

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      PilotBlockLengthinteger in the range [1, 255]

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — Length of the pilot block, in symbols, returned as an integer in the range [1, 255].

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      PermutationParametersfive-element vector

      When you set the TransmissionFormat property of the object to "TC-LM" or "SS-TC-LM" — DVB-RCS2 turbo encoder permutation control parameters used to generate turbo encoder interleaver indices, returned as a 5-element vector in order: P, Q0, Q1, Q2, and Q3.

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      ModulationIndex"1/5", "1/4", "2/7", "1/3", or "2/5"

      Modulation index of the CPM modulator, returned as "1/5", "1/4", "2/7", "1/3", or "2/5".

      "When you set the TransmissionFormat property of the object to "CC-CPM" — This field is not applicable."

      EncoderConstraintLength"3" or "4"

      Encoder constraint length based on the convolutional coding type, returned as one of these options.

      • "3" — Returned when the convolutional coding coefficients (in octal) are (5,7).

      • "4" — Returned when the convolutional coding coefficients (in octal) are (15,17).

      This field is applicable when you set the TransmissionFormat property of the object to "CC-CPM".

      PhaseResponseCoefficient"0.625", "0.75", or "0.98"Raised cosine filter coefficients weightage of the pulse-shaping filter, returned as "0.625", "0.75", or "0.98".
      NumTrellisTerminationBits"4" or "6"

      The number of additional tail bits passed into the CPM modulator for phase trellis termination, returned as one of these options.

      • "4" — Returned when the WaveformID property is set to 4, 7, 10, 13, 16, or 19.

      • "6" — Returned if the WaveformID property has any other value.

      This field is applicable when you set the TransmissionFormat property of the object to "CC-CPM".

      UniqueWordcharacter array or string scalarHexadecimal string consisting of the combined symbols of the preamble, one pilot block, and the postamble sequence, returned as a character array or string scalar.

    • If obj is a ccsdsTMWaveformGenerator System object, the output structure has these fields, consisting of physical layer information about the Consultative Committee for Space Data Systems (CCSDS) Telemetry (TM) waveform generator.

      FieldValueDescription
      ActualCodeRatepositive scalar in range [0 1]Numeric value of the code rate of the channel coding scheme, returned as a positive scalar in the range [0, 1]. This value is used to generate the CCSDS TM waveform.
      NumBitsPerSymbolpositive integerNumber of bits per modulated symbol, returned as a positive integer.
      SubcarrierFrequencypositive scalarSubcarrier frequency, returned as a positive scalar. This field is applicable only when the Modulation property of ccsdsTMWaveformGenerator object is set to "PCM/PSK/PM". For other cases, this value is returned as null.

    • If obj is an etsiRicianChannel System object, the output structure has these fields, consisting of information about the fading channel.

      FieldValueDescription
      ChannelFilterDelay0Channel filter delay in samples returned as 0 always (due to flat fading nature of the channel).
      ChannelFilterCoefficients1Channel filter coefficient used to convert path gains to channel filter tap gains, returned as 1 always (as etsiRicianChannel describes a single path channel).
      NumSamplesProcessednonnegative integerNumber of samples processed by the channel object since the last reset, returned as a positive integer.

    • If obj is a p681LMSChannel System object, the output structure has these fields, consisting of information about the ITU-R P.681-11 land-mobile satellite (LMS) fading channel.

      FieldValueDescription
      PathDelays0Delay of discrete channel path in seconds returned as 0 always (due to flat fading nature of the channel).
      ChannelFilterDelay0Channel filter delay in samples returned as 0 always (due to flat fading nature of the channel).
      ChannelFilterCoefficients1Channel filter coefficient used to convert path gains to channel filter tap gains, returned as 1 always (as p681LMSChannel describes a single path channel).
      NumSamplesProcessednonnegative integerNumber of samples processed by the channel object since the last reset, returned as a nonnegative integer.

    • If obj is a lutzLMSChannel System object, the output structure has these fields, consisting of information about the Lutz LMS fading channel.

      FieldValueDescription
      PathDelays0Delay of discrete channel path in seconds returned as 0 always (due to flat fading nature of the channel).
      ChannelFilterDelay0Channel filter delay in samples returned as 0 always (due to flat fading nature of the channel).
      ChannelFilterCoefficients1Channel filter coefficient used to convert path gains to channel filter tap gains, returned as 1 always (as lutzLMSChannel describes a single path channel).
      NumSamplesProcessednonnegative integerNumber of samples processed by the channel object since the last release or reset, returned as a nonnegative integer.

    • If obj is a gpsPCode System object, the output structure has these fields, consisting of state information about the GPS P-code generator.

      FieldValueDescription
      TotalNumChipsElapsedpositive integerTotal number of P-code chips that elapsed from the beginning of the week, returned as a positive integer. The beginning of a week is marked at midnight Saturday night - Sunday morning.
      TotalSecondsElapsedreal-valued scalarTotal seconds elapsed from the beginning of the week, returned as a real-valued scalar.

    • If obj is a gpsWaveformGenerator System object, the output structure has these fields, consisting of state information about the GPS waveform generator.

      FieldValueDescription
      CurrentTimereal-valued scalar

      The current time of the week in seconds, returned as a real-valued scalar.

      SecondsElapsedreal-valued scalar

      Time elapsed, in seconds, for which the waveform has been generated from the beginning of object creation or from the last reset, returned as a real-valued scalar.

      NumBitsProcessedreal-valued scalar

      Number of input bits for which the waveform has been generated from the beginning of object creation or from the last reset, returned as a real-valued scalar.

      NumBitsProcessed is calculated as round(SecondsElapsed/B) where B is the BitDuration property of the object.

    • If obj is a gnssSignalAcquirer System object, the output structure has this field, consisting of information about the GNSS signal acquisition.

      FieldValueDescription
      ReferenceNoiseLevelnumeric scalar

      Reference noise level in the incoming signal, returned as a numeric scalar.

      The info function calculates the reference noise level value by correlating the incoming signal with a C/A-code which is not present in the signal. The function uses G1-code to generate the C/A-code. The reference noise level is the peak of such correlation values.

    Version History

    Introduced in R2021a

    See Also

    Functions

    Objects