CA250 Bit Stream Analysis by Rohde & Schwarz

Companies & Organizations:


Rohde & Schwarz GmbH & Co KG
Muehldorfstrasse 15
81671 Muenchen

In the field of technical analysis of modern communications signals, the ability to analyze the characteristics of demodulated signals with unknown codings is of major importance. In addition to various symbol stream/bitstream representations, R&S®CA250 provides a large number of powerful analysis algorithms and bitstream manipulation functions.


By selectively using these tools, the user can obtain technical data from the unknown bit stream. This data provides information about the type and content of the analyzed signal. Ideally, it is possible to resolve all aspects of the unknown code, thereby allowing the user to program a specific decoder for the unknown signal (e.g. by using the R&S®GX400ID decoder development environment).


Key Facts


Import of various symbol stream/bit stream formats

Symbol-to-bit mapping and bit stream representation

Versatile bitstream analysis functions

Wide variety of bit manipulation functions

Integration of user-specific algorithms into the R&S®CA250 operation sequences

Programmable script control for performing automatic analysis sequences


Features & Benefits


Versatile data import and symbol stream/bitstream representation

- Import of various symbol stream/bitstream formats

- Symbol-to-bit mapping and bitstream representation as 0/1 and -/X representation as well as graphical visualization


Versatile bitstream analysis functions

- Structure analysis

- Statistical methods


Advanced code analysis functions

- Automatic recognition of channel codings (convolutional, Reed-Solomon codes, etc.)

- Manual expert analysis tools


Wide variety of processing functions for channel-coded bitstreams

- Standard manipulation such as deletion, inversion, multiplexing and demultiplexing

- Complex bitstream processing methods such as descrambling, deinterleaving

- Processing of channel codings (convolutional, Reed-Solomon and other codes)


Payload analysis and processing

- Automatic detection of typical payload structures

- Various alphabets

- Digital voice codecs

- Processing of compressed data


Automation, extensibility and versatility

- Integration of user-specific algorithms into the R&S®CA250 operation sequences

- Programmable script control for performing automatic analysis sequences

- Various user-configurable and extensible functions




R&S®CA250 bitstream analysis


Analysis algorithms             Autocorrelation


                                            Configurable pattern search

                                            Tsallis entropy

                                            Maurer test

                                            Chi-square test


                                            Calculation of column sum/parity

                                            Calculation of line sum/parity

                                            automatic peak and notch detection for diagrams

Decoder and                       Symbol-to-bit conversion

manipulation functions       Conversion of differential coding to absolute coding

                                            Line codes




                                            Boolean operations


                                            basic demultiplexing

                                            Extract items

                                            Symbol-to-symbol mapper

                                            Symbol adder

                                            Channel serialization

                                            ASCII alphabet

                                            Baudot (ITA2) alphabet

                                            ITA3 alphabet

                                            ITA476-5 alphabet

                                            ITA2-P alphabet

                                            RUM-FEC alphabet

                                            HNG-FEC alphabet

                                            Varicode alphabet

                                            Huffmann alphabet

                                            user-defined alphabets

Representation                   Symbol stream/bitstream in tabular form

                                            Decimal representation (0/1)

                                            Hexadecimal representation

                                            –/X representation

                                            Graphical visualization

                                            Display of demodulation quality as color-coded background

                                            Tags for start-of-burst

                                            Tags for the first channel (in multichannel methods)

                                            Zoom functions

                                            Line charts

                                            Window for displaying decoded text

                                            tabular data display for analysis and protocol data

System functions                 Generation of reports in XML format (compatible with R&S®ReportEdit)

Recommended computer equipment

Operating system                 Windows

CPU (minimum)                   Intel Pentium IV, 3 GHz

Memory (minimum)              1 Gbyte

Graphics card                        OpenGL 1.4 capable

Hard disk memory                 500 Mbyte (for installing R&S®CA250)


Minimum screen resolution   1024 pixel × 768 pixel

Sound playback                     Sound card


R&S®CA250-E extended bitstream analysis

Analysis algorithms             Search for CRC codes

                                            Search for BCH codes

                                            Search for Reed-Solomon codes

                                            Analysis of rate 1/N convolutional codes

                                            Analysis of 1/N to rate K/N punctured convolutional codes

                                            Analysis of rate K/N convolutional codes

                                            Search for the most common polynomials

Decoder and                        Block interleaving

manipulation functions         Block interleaver with skip bits

                                            Cross interleaving

                                            Convolutional interleaving

                                            Helical interleaving

                                            CRC decoder

                                            BCH decoder

                                            Reed-Solomon decoder

                                            Viterbi decoder with/without puncturing

                                            Golay decoder

                                            bit destuffing


R&S®CA250-P professional bitstream analysis

Analysis algorithms              Analysis of additive scrambling

                                            Analysis of multiplicative scrambling

                                            Analysis of spread spectrum code (DSSS)

Decoder and                       Additive descrambling

manipulation functions        Multiplicative descrambling


                                            A-law/μ-law voice codec (in line with ITU G.711)

                                            ADPCM voice codec (in line with ITU G.726)

                                            LD-CELP voice codec (in line with ITU G.728)

                                            CVSD voice codec (in line with STANAG 4209)

                                            LPC-10 voice codec (in line with STANAG 4198)

                                            MELP voice codec (in line with STANAG 4591)

Representation                    Audio player for playing back decoded voice codecs


R&S®CA250-PA payload analysis

Analysis algorithms             bit-error-tolerant file detection

Decoder and                        LZRW1-3

manipulation functions        Deflate


                                            Sequence generator


R&S®CA250-CA code analysis

Analysis algorithms             code classifier

                                            bit-error-tolerant convolutional code analysis

                                            polynomial factorization

                                            polynomial division

greatest common divisor

                                               code word statistics (mean value, variance)

                                            minimum distance analysis

                                            uniform sequence length analysis

Decoder and                        advanced demultiplexing

manipulation functions        descrambling (in line with ITU-T V.35)

                                            convolutional decoder (in line with IESS.303)

                                            LDPC decoder

                                            repetition decoder

                                            Walsh decoder


R&S®CA250-D development edition

System functions                 application automation via script control (Python)

                                            linking of customer-specific algorithms via

                                            Windows DLL interface


R&S®CA250-U licensing option

Option for licensing R&S®CA250 with a USB dongle with 2 Gbyte additional memory

Interface                              USB 2.0

Dimensions (W × H × D)     8 mm × 16 mm × 52.5 mm (0.31 in × 0.63 in × 2.07 in)

Defense Products & Services: CA250 Bit Stream Analysis by Rohde & Schwarz
Companies & Organizations: 
Defense Products & Services Sectors: Computers software
Country: Germany
Description: CA250 Bit Stream Analysis
Source of Information: Rohde & Schwarz GmbH & Co KG