ccsdsTCIdealReceiver

Ideal receiver for CCSDS TC waveform

Since R2021a

Syntax

bits = ccsdsTCIdealReceiver(waveform,cfg)

bits = ccsdsTCIdealReceiver(waveform,cfg,Name,Value)

Description

bits = ccsdsTCIdealReceiver(waveform,cfg) recovers transfer frames from a Consultative Committee for Space Data Systems (CCSDS) Telecommand (TC) waveform, generated using the ccsdsTCWaveform function. Output bits is the recovered bits for the given format configuration cfg.

bits = ccsdsTCIdealReceiver(waveform,cfg,Name,Value) specifies options using one or more name-value pairs. For example, 'NoiseVariance',1e-11 specifies the noise variance of additive white Gaussian noise (AWGN) on the received waveform as 1e-11.

Examples

Recover Transfer Frame from CCSDS TC Waveform

Recover the transfer frame from the Consultative Committee for Space Data Systems (CCSDS) Telecommand (TC) waveform.

Create a CCSDS TC object and specify the object properties.

cfg = ccsdsTCConfig;
cfg.HasRandomizer = 1;
cfg.SamplesPerSymbol = 12;
disp(cfg)

  ccsdsTCConfig with properties:

             DataFormat: "CLTU"
          ChannelCoding: "BCH"
          HasRandomizer: 1
             Modulation: "PCM/PSK/PM"
              PCMFormat: "NRZ-L"
        ModulationIndex: 0.4000
    SubcarrierFrequency: 16000
             SymbolRate: 4000
       SamplesPerSymbol: 12

   Read-only properties:
     SubcarrierWaveform: "sine"

Specify the transfer frame length and generate the CCSDS TC waveform for the transfer frame.

transferFrameLength = 12; % Number of octets in each transfer frame
data = randi([0 1],8*transferFrameLength,1); % bits in the transfer frame
waveform = ccsdsTCWaveform(data,cfg);

Recover the transfer frame from the CCSDS TC waveform

decodedBits = ccsdsTCIdealReceiver(waveform,cfg,'DecodingMode',"error detecting");

Check if the transfer frame is recovered successfully.

rxBits = decodedBits{1};
bits = rxBits((1:8*transferFrameLength)');
isequal(bits,data)

ans = logical
   1

Input Arguments

waveform — Received time-domain signal

column vector

Received time-domain signal, consisting of complex in-phase quadrature (IQ) samples, specified as a column vector. The waveform input is a CCSDS TC waveform.

A CCSDS TC waveform can contain one or more communications link transmission units (CLTUs). Each CLTU can contain one or more transfer frames.

Data Types: single | double
Complex Number Support: Yes

cfg — Format configuration object

ccsdsTCConfig object

Format configuration object, specified as ccsdsTCConfig object. The properties of this object determine the parameters required for CCSDS TC waveform generation and reception.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: ccsdsTCIdealReceiver(waveform,cfg,'NoiseVariance',1e-11) specifies the noise variance of AWGN on the received waveform as 1e-11.

NoiseVariance — Noise variance of AWGN

1e-10 (default) | positive scalar

Noise variance of AWGN that is added to the input IQ symbols of the waveform, specified as a positive scalar.

Dependencies

To enable this name-value pair, set the ChannelCoding property of the cfg input to "LDPC".

Data Types: double

DecodingMode — Decoding mode

"error correcting" (default) | "error detecting"

Decoding mode to decode the Bose Chaudhuri Hocquenghem (BCH) encoded codewords, specified as "error correcting" or "error detecting".

'DecodingMode' defines the allowed number of errors in the start sequence of the CLTU. In error detecting mode, the allowed number of errors in the start sequence is zero. In error correcting mode, the allowed number of errors in the start sequence is one.

Dependencies

To enable this name-value pair, set the ChannelCoding property of the cfg input to "BCH".

Data Types: char | string

DetectionThreshold — Threshold to detect start sequence

0.7 (default) | scalar in the range [0.5, 1]

Threshold to detect the start sequence, by calculating the normalized correlation metric with the known start sequence, specified as a scalar in the range [0.5, 1]. When the computed normalized correlation metric is greater than or equal to 'DetectionThreshold', the start sequence of the CLTU is detected.

Dependencies

To enable this name-value pair, set the ChannelCoding property of the cfg input to "LDPC".

Data Types: double

Output Arguments

bits — Recovered transfer frames

cell array of column vectors

Recovered transfer frames, returned as a cell array of column vectors. Each element of the cell array is of data type int8.

Bits in the cell array of one or more column vectors, corresponds to the number of CLTUs present in the waveform input. Recovered transfer frames of CLTUs can contain fill bits. The fill bits removal procedure is not performed in the TC synchronization and channel coding sublayer.

Data Types: int8 | cell

References

[1] CCSDS 231.0-B-3. Blue Book. Issue 3. "TC Synchronization and Channel Coding." Recommendation for Space Data System Standards. Washington, D.C.: CCSDS, September 2017.

[2] CCSDS 401.0-B-29. Blue Book. Issue 29. "Radio Frequency and Modulation Systems - Part 1". Earth Stations and Spacecraft. Washington, D.C.: CCSDS, September 2019.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2021a