Simulation of a baseband QPSK mod/demod: TX : a pseudo random bit stream generation, Serial to parallel conversion, QPSK Mapping (Gray coding), Signal power computation Channel : AWGN channel RX: Soft Demapping / Hard Demapping, Plot constellat

serial to parallel converter

The implementation was built on Matlab/Simulink using fundamental components in Simulink to demonstrate how reliably complex modulation schemes can be built, cost effectively and efficiently [5]. The design of ZigBee transmitter using MSK mod

正交频分复用(OFDM)技术是一种可以有效对抗符号间干扰(ISI)的高速数据传输技术。OFDM是一种特殊的多载波调制方式，它的基本思想是将高速传输的数据流通过串/并转换，变成在若干个正交的窄带子信道上并行传输的低速数据流。OFDM接收机有三个关键技术：信道估计技术，降低峰均比(PAPR)技术和同步技术。OFDM技术能有效的对抗多径衰落等，有着诸多的优点，但是OFDM有一个发展瓶颈，即OFDM信号的峰均功率比很大，很容易导致OFDM信号的交调失真和系统性能的下降。因而如何降低OFDM信号的峰均功率

ofdm仿真，用matlab仿真实现ofdm，为初学者提供一条道路(The proposed secret data embedding and extraction in OFDM is shown in figure 1.In order to achieve higher data rate, the serial data stream bits are converted in to parallel data output bits. Then the modulation s