Computes BER v EbNo curve for convolutional encoding / soft decision
Viterbi decoding scheme assuming BPSK.
Brute force Monte Carlo approach is unsatisfactory (takes too long)
to find the BER curve.
The computation uses a quasi-analytic (QA) technique that relies on the
estimation (approximate one) of the information-bits Weight Enumerating
Function (WEF) using
A simulation of the convolutional encoder. Once the WEF is estimated, the analytic formula for the BER is used.
This program simulates the bit-error-rate (BER) performance of OSTBC
with L=4 antennas over the frequency flat Rayleigh block fading channel
The code is developed for real orthogonal design, code rate 1/2
modulation- 16 QAM with gray coding resulting in 2 bits/sec/Hz.
NRF905驅動代碼
// The content of this struct is nRF905 s initialize data.
// CH_NO=1 433MHZ Normal Opration,No Retrans RX,TX Address is 4 Bytes
// RX TX Payload Width is 32 Bytes Disable Extern Clock Fosc=16MHZ
// 8 bits CRC And enable
I ve written some many years ago dynamic Huffman algorithm to compress and decompress data. It is mainly targeted to data with some symbols occuring more often than the rest (e.g. having some data file consisted of 3 different symbols and their total number of occurence in that file s1(1000), s2(200), s3(30) so the total length of file is 1000+200+30=1230 bytes, it will be encoded assigning one bit to s1 and 2 bits to s2, s3 so the encoded length will be 1*1000+2*(200+30)=1460 bits=182 bytes). In the best case the file consisted of just one symbol will be encoded with compression ratio as 1:8. Huffman coding is used in image compression, however in JPEG2000 arithmetic codec is imployed.
As mentioned, most computers include a serial port. The only hardware setup required is connecting the serial cable to the serial port on the PC and the serial port on the instrument. The serial instrument may include some hardware drivers or software utilities for communication, and should include documentation on the baud rate, packet size, stop bits, and parity bits that the instrument will use. Additionally, check the National Instruments Instrument Driver Network to see if LabVIEW drivers already exist for yout instrument, as
This file contains a C++Builder 4 project called SimplyChaos-X ver 3.1 (SCX31).
SCX31 is an encryption tool. I designed it as my graduation paper work. SCX31 is a symmetric stream cipher built on chaos function, one time pad cipher and inspiration from Ground Effect (aviation). The key length can be up to 40 characters (320 bits).
Digital Signature Algorithm (DSA)是Schnorr和ElGamal簽名算法的變種，被美國NIST作為DSS(DigitalSignature Standard)。算法中應用了下述參數：
p：L bits長的素數。L是64的倍數，范圍是512到1024；
q：p - 1的160bits的素因子；
g：g = h^((p-1)/q) mod p，h滿足h < p - 1, h^((p-1)/q) mod p > 1；
x：x < q，x為私鑰 ；
y：y = g^x mod p ，( p, q, g, y )為公鑰；
H( x )：One-Way Hash函數。DSS中選用SHA( Secure Hash Algorithm )。
p, q, g可由一組用戶共享，但在實際應用中，使用公共模數可能會帶來一定的威脅。簽名及驗證協議如下：
1. P產生隨機數k，k < q；
2. P計算 r = ( g^k mod p ) mod q
s = ( k^(-1) (H(m) + xr)) mod q
簽名結果是( m, r, s )。
3. 驗證時計算 w = s^(-1)mod q
u1 = ( H( m ) * w ) mod q
u2 = ( r * w ) mod q
v = (( g^u1 * y^u2 ) mod p ) mod q
若v = r，則認為簽名有效。
DSA是基于整數有限域離散對數難題的，其安全性與RSA相比差不多。DSA的一個重要特點是兩個素數公開，這樣，當使用別人的p和q時，即使不知道私鑰，你也能確認它們是否是隨機產生的，還是作了手腳。RSA算法卻作不到。
Flash中內置了一個狀態寄存器（Status Register，SR）來指示Flash的當前工作狀態和各種操作是否成功。要讀取SR的當前值需要向CUI發送讀狀態寄存器命令（Read Status Register），命令碼為0x70，SR中的內容將在DQ[7:0]上輸出。The Read Status Register （0x70）command causes subsequent reads to output data from the SR until another command is issued. The SR bits are output on DQ[7:0].
The acceptance and introduction of serial communication to more and more
applications has led to requirements that the assignment of message identifiers to
communication functions be standardized for certain applications. These applications
can be realized with CAN more comfortably, if the address range that originally has
been defined by 11 identifier bits is enlarged
