QPSK-OFDM

In this paper, we present and analyze efficient frame synchronization and frequency offset compensation scheme with ternary sequences for an orthogonal frequency division multiplexing (OFDM) system in Rayleigh fading channels. Frame synchronization is an essential procedure for normal operation of the OFDM system because of sensitivity to synchronization errors. And when there are frequency offsets in OFDM frame, the loss of orthogonality occurs and the interference problem among several subcarriers is introduced. These fact leads to the requirement for joint implementation of the frame synchronization and frequency offset compensation.

采用BPSK调制技术，用ZF和ZF加并行干扰消除的方法检测系统的误码率。(Using BPSK modulation technique, with the ZF and ZF plus parallel interference cancellation method to detect the BER.)

CA 码的产生，以及自相关，互相关函数，画出自相关互相关图（MATLAB语句简单易懂，适合新手）(CA code generation, as well as autocorrelation, cross-correlation function, drawn from the correlation cross correlation diagram (MATLAB statement, easy to understand, suitable for novices))

GSM Security and the protocols involves in a mobile environment authentication process

HDLC控制协议中CRC校验码算法代码，为CRC16，Verilog语言(HDLC Control Protocol Code in the CRC checksum algorithm code for CRC16, Verilog language)

说明：  无源被动雷达定位中的利用椭圆法求交点，得到目标位置(Passive Radar Detection using Range-Doppler Transformations find ell intersect)

base is now HeapNumber with valid Smi value.

a matlab code for spatial modulation

说明：  脉冲压缩的匹配滤波。目标距离分别为10米，30米和100米，对于未压缩的脉冲，三个回波信号混叠在一起，不能分辨，而经过脉冲压缩的脉冲信号则可通过匹配滤波收到3个回波信号(Matched filtering for pulse compression.Target distances are 10 metres, 30 metres and 100 metres, respectively. For uncompressed pulses,The three echo signals are overlapped and can not be distinguished. While pulse compression can distinguish three echo signals after matched filtering)

16QAM数字基带信号系统仿真，包括发射机程序和接收端程序(16QAM digital baseband signal system simulation)