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语音数据包大小和语音活动检测的作用

在通信技术刚发展起来的那些年，我们使用有线网络通信，而如今技术发达了。目前，我们使用无线网络来进行通信。早些年，我们使用不同的技术，像公用交换电话网（PSTN）将语音数据包从源端传送到目的端，但这些技术都有一些缺陷，比如信号丢失、时间延迟、有杂音等，这些都使语音传输质量低下。为了克服这些缺陷，我们引进了一项新技术VoIP（互联网语音传输协议）。

通过这项技术，我们将声音从模拟信号转化为数据信号，然后变成数据包，数据包A将通过IP网络（i.e网络）在发送者和接收者之间进行传输。发送者利用路由器发出信号，接收者通过解码获得语音信息，反之亦然。在整个传输过程中，需要一个媒介，这个媒介就是互联网络或者分封交换网络。通过这种技术，我们可以将语音数据包变得更清晰，所以接收者可以收到无干扰的清晰语音。

Effect Of Voice Packet size and Speech Activty Detection
Published: 23, March 2015

In the early days of communications we used the wire networks for communication but now the technology has been developed. Now a days we are using the wireless techniques for the communications. In the earlier days we have used different techniques like PUBLIC SWITCHED TELEPHONE NETWORK (PSTN) for the transfer of voice packets from source to destination but due to these techniques there are some draw backs like loss of siganl, time delay, noice and many other which will result in the transfer of the voice with poor quality. To over come these drawbacks one new technology is introduced that is VoIP(voice over internet protocol).

By using this technique we will convert the voice which is an analog signal to a digital signal and then to a voice packet the voice packet  is transmited through the Ip network (i.e Internet) from the sender to the recevier using a router and the recievier wil decode it in vice versa for the whole process it needs a medium and the medium it is using is internet or packet switched network. Due to this type of technique we can send the packet with more clarity so that the recvier will have a clear vioce with out any disturbance.

The main advantage of the VoIP is that it does not require any dedicated packet switching path.. PSTN uses 64 kbps of band width over a circuit switched connection and the path should be given to it until it is terminated but in the VoIP that is not the case it doesnot require any dedicated path but it only requires only sufficient bandwidth.

The silent packets are the main cause for the traffic problems. Since if there are more silent packets then the congestion will be increased in the network the but in the VoIP that is not the case it will not generate any silent packets, it uses different technique to over come in this problem.

VoIP STANDARDS :
               VoIP has two main standards. by using those standards audio encoding is done. ITU (International Tele-communication Union) and IETF(Internet Engineering Task Force)these are the two encoding schemes used in VoIP. This can be done by PCM (Pulse Code Modulation) and after encoding the voice packet and converting into digital packet RTP (Real Time Transfer Protocol) is used to transfer it over the IP networkVOIP standards are used in protocols. There are many protocols like H.323, SIP, MGCP etc

H.323 (Horizon):
            It uses ITU-T standard. It will manage the telephone standards. In the earlier days this was used on local area networks for Multimedia conferencs. But now a days the usage of this standard is more so this was modified and used in the VoIP.

SIP (Session Initiation Protocol): this is mainly made for session It本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。