Codewords and Layers and Ports

We throw a lot of terms around when we discuss LTE data transmissions, especially when we get into some of the details of sending data over the PDSCH using multiple antenna techniques. We describe transport blocks as holding the data we’re trying to send, but how do they relate to codewords? Assigning bits to different layers can be used to improve reliability or throughput, but are layers the same as antenna ports? Let’s have a closer look at what’s going on down in the Physical (PHY) Layer.

User data and signaling messages are processed by the PDCP, RLC and MAC layers before being passed down to the PHY layer to be sent over the air. A lot happens to a data packet before PHY gets it, but for the moment, let’s just treat the MAC PDU (Protocol Data Unit) that PHY receives from MAC as “data”. To PHY, it’s just a string of bits anyway. This will be our transport block. Read more

CRC字节算法

在研究CRC字节算法的时候参考了网上的一些博客,但是感觉写的不够透彻,有的也出现一些错误。本文的目的是详细讲解CRC字节算法。

有关CRC算法的介绍请参见:

参考链接一:最通俗的CRC校验原理剖析

参考链接二:CRC查找表法推导及代码实现比较

在此,强调一下CRC算法中两个重要的点:

1、 原始序列要左移n位,再除以生成多项式;

2、生成多项式所包含的比特数比CRC校验比特数多1。

以上两点注意事项可在最通俗的CRC校验原理剖析中的例子观察。

在证明之前,先复习一下取余运算的计算法则:

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在Code Composer Studio(CCS) 5.3中设置target configuration的步骤

本文为原创,转载请注明作者和出处!

在本文中将详细介绍如何在Code Composer Studio (CCS)中设置下载用的target configuration和仿真用的target configuration。

环境:

开发板:TMDSEVM6670LE

模拟器:XDS560v2 Emulator

电源: 自带电源

下载用的target configuration

步骤:

  • Step 1:在CCS 5.3中将界面切换到CCS Debug,这个按钮在软件界面的右上角。如果没有,请点击”CCS Edit”左边的添加按钮,将CCS Debug加上去。按钮如下图所示。

1

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