User manual WAVECOM W-BV BITVIEW VERSION 2.3.0

[. . . ] BitView Manual V2. 3. 00 WAVECOM W-BV by WAVECOM ELEKTRONIK AG PUBLISHED BY WAVECOM ELEKTRONIK AG Hammerstrasse 8 CH-8180 Buelach Switzerland Phone Fax Email: Internet: +41-44-872 70 60 +41-44-872 70 66 info@wavecom. ch http://www. wavecom. ch © by WAVECOM ELEKTRONIK AG. Reproduction in whole or in part in any form is prohibited without written consent of the copyright owner. The publication of information in this document does not imply freedom from patent or other protective rights of WAVECOM ELEKTRONIK AG or others. All brand names in this document are trademarks or registered trademarks of their owners. [. . . ] The easiest way to understand the de-interleaving stream function is a closer look at the example below (imagine that the bit stream is written horizontally into the buffer and read out vertically): Example 1: Offset into Bit Buffer = 0 Interleaving distance = 15 Output frame length = 4 Example 2: Offset into Bit Buffer = 3 Interleaving distance = 8 Output frame length = 4 AND / OR / XOR / NOT In: Bit stream Out: Bit stream Function: BitView Manual V2. 3. 00 WAVECOM W-BV Function Library 33 The output bit values depend on the selected logical operation (Logical operator) performed on the input bits. The first operand is the input bit stream, while the second operand (Frame) is constant and can be either , , 0 or , , 1. AND / OR / XOR / NOT Range In: Bit stream Out: Bit stream Function: The output bit values depend on the selected logical operation (Logical operator) performed on the input bits from Offset to first frame and over Number of frames. The first operand is the input bit stream, while the second operand (Frame) is constant and can be , , 0 or , , 1. Extraction (Mask) In: Bit stream Out: Bit stream Function: Extracts bits from the incoming bit stream using the user defined Mask. Example: "111110" with mask "110" changes to "1111". Extraction (Range) In: Bit stream Out: Bit stream Function: 34 Function Library BitView Manual V2. 3. 00 WAVECOM W-BV Extract Extraction length bits from the incoming bit stream starting at Extract start position. Cutting In: Bit stream Out: Bit stream Function: Cuts Cut length bits, beginning at Cut start position. Note that counting starts at zero, i. e. , the first element in the bit stream is number 0. Decoding/Equalizer Viterbi-Decoding In: Bit stream Out: Bit stream Function: Decode the incoming bit stream using the Viterbi algorithm - a maximum-likelihood decoding procedure for convolutional codes. Parameter Constraint length Decision best state Last decoder state Metric Mode Soft decision bits Equals n+1, where n is the length of the shift register in the encoder Use best state or not Initial state of the decoder Select hard or soft decision Select whether the input data should be treated as a continuous stream or a stream of bursts. If soft decision is used, enter the number of soft decision bits De-Puncturing In: Bit stream Out: Bit stream BitView Manual V2. 3. 00 WAVECOM W-BV Function Library 35 Function: This function adds de-puncturing bits and probability bits to the input bit stream. Parameter Frame Value Bits are inserted according to the entered bit pattern. For received bits (marked with a , , 1 in the frame pattern), a , , 1 probability bit is added - for inserted bits, a , , 0 probability bit is added (equals a probability of 0. 5) Example with a frame pattern of "110": The frame pattern "110" means that after two input bits, a de-puncturing bit must be inserted so "1111" becomes "111100111100". Difference-Decoding In: Bit stream Out: Bit stream Function: This function performs difference decoding, which is a logical XOR operation on the previous output bit and the current input bit. Example with start bit value of , , 1: "01101110" is changed to "10110100". BCH-Decoding In: Bit stream Out: Bit stream 36 Function Library BitView Manual V2. 3. 00 WAVECOM W-BV Function: Decodes BCH encoded bit streams. Parameter Corrected errors Error Positions Generator Polynomial Minimum distance Number of frames Order of Galois field Original data length Primitive polynomial Description Number of corrected errors Positions of detected errors Encoding generator polynomial on the form g(x) = 111. . . This property determines the number of detectable errors and the number of correctable errors Number of frames in the decoded bit stream Property of the field of numbers to which a given BCH code belongs Length of original code word A polynomial describing a given BCH code Parameter BCH algorithm Code word length Max errors Description Algorithm used to find BCH polynomial Length of code word including redundancy bits. Error correction capability Value Berlekamp-Massey, Euclid Example with code length 15 and error correction capability 3: "011001010000111" is changed to "00111". Block Code Analysis In: Bit stream Out: Bit stream Function: BitView Manual V2. 3. 00 WAVECOM W-BV Function Library 37 Identify forward error correction block codes like BCH, RS, CRC or Hamming. The function returns alphabet size (normally equal to 2 because input is a binary bit stream), block code type (BCH, RS, etc. ), code word length estimation (n), generator polynomial, input length estimation (k) and code rate estimation (R = k/n). The function will identify the following Block Code Types, Unidentified code BCH CRC or perfect cyclic code Binary repetition (reversals) Binary Golay Binary Hamming CRC block code Non-cyclic block code The generator polynomial is returned as a string of ones and zeros, starting at the lowest order of 2^x, e. g. , 1001110010101 means 1 + x^3 + x^4 + x^5 + x^8 + x^10 + x^12. The results of the analysis are displayed in a new document window and in the Calculation category in the Properties window. Parameter Alphabet size Block code type Codeword length estimation Generator polynomial Input length Rate estimation Description Size of input alphabet Type of block code used Length of input code word (n) , i. e. , number of data bits (k) plus number of checksum bits (n-k) Generator polynomial (G(x)), i. e. , the polynomial used to generate the checksum Estimated number of data bits per code word Code rate (R = k/n), i. e. , ratio between number of data bits (k) and total number of bits per frame (n+k) Constraints: Frames must have equal length and if the bit stream is delimited by flags they must be removed with the Extract or Cut functions. Convolutional Code Analysis In: Bit stream Out: Bit stream Function: Find the parameters of convolutional encoded bit streams. The function returns constraint length (K), number of input bits per shift cycle (k), number of output bits per shift cycle (n) and generator polynomials. The numbers of returned generator polynomials depend on the number of output bits per shift cycle (n). The results of the analysis are displayed in a new document window and in the Calculation category in the Properties window. The table below lists the calculated parameters. 38 Function Library BitView Manual V2. 3. 00 WAVECOM W-BV Parameter Gen. Poly4 Input bits (k) Constraint length (K) Output bits (n) Description Generator polynomial 1 found Generator polynomial 2 found Generator polynomial 3 found Generator polynomial 4 found Number of input bits to convolutional encoder Constraint length, i. e. , the number of bit in encoder memory affecting the generation of n output bits Number of output bits from convolutional encoder General Reed Solomon Decoding In: Bit stream Out: Bit stream Function: Decodes bit streams which are encoded with a Reed-Solomon code. [. . . ] Configuration Proxy Proxy support Proxy Server Proxy Port Authentication Proxy User Proxy Password Remarks Enable or disable Proxy Server support; this option has to be enabled if you are using a proxy server Set the IP address of your proxy server Set the port number of your proxy server Enable or disable the proxy server authentication User ID for the proxy server User password for the proxy server The Access Control sub-section. 80 Appendix BitView Manual V2. 3. 00 WAVECOM W-BV Configuration Access Control Clients Remarks Shows a list of all CodeMeter client computers that have permission to use the CodeMeter Server (check out a license) If this list is empty (default setting), all CodeMeter Clients are allowed to use the CodeMeter Server. To allow a special CodeMeter Client to use the CodeMeter Server, just click on the "Add" button and enter the IP address or the DNS name of the client into the input box. To remove a Client, highlight its IP address and click "Remove". If this feature is enabled (box is checked), CodeMeter Clients or developer PCs can access the CodeMeter Firm Security Box (FSB). [. . . ]