For Push-To-Talk (PTT) system based on Public Mobile Data Network (PMDN), the end-to-end time delay is the key aspect of the user's experience. The Push-Over-Cellular (POC) scheme defined by Open Mobile Alliance (...For Push-To-Talk (PTT) system based on Public Mobile Data Network (PMDN), the end-to-end time delay is the key aspect of the user's experience. The Push-Over-Cellular (POC) scheme defined by Open Mobile Alliance (OMA) is based on the VoIP phone model and use SIP protocol as the call control scheme. The call setup time delay in SIP may reach to several seconds, which is unac-ceptable for the PTT service. In this paper, we provide a new call control scheme for PTT system based on PLMN network. By combining the apriority knowledge of PTT call model and the priority control scheme, we encapsulate the signaling message and the voice data into a same data packet, when the user push the button, the voice and the call control signaling are sent to the server at the same time. So the long time delay of call setup procedure of POC scheme can be eliminate. The end-to-end call delay can be decreased significantly. The experiment result based on the commercial CDMA2000 1X network of China Unicom shows that the call delay can be decreased to 600 ms, which approach to the traditional trunk communication system's requirement.展开更多
“长江，长江，我是黄河，收到请回复。”……这个耳熟能详的电影对白如果随时随刻在我们身边出现，大家一定会觉得是对讲机发烧友们的恶作剧：再如果某天看到某人打开手机的第一件事不是拨打电话，而是打开了类似QQ中常用的群组功能，...“长江，长江，我是黄河，收到请回复。”……这个耳熟能详的电影对白如果随时随刻在我们身边出现，大家一定会觉得是对讲机发烧友们的恶作剧：再如果某天看到某人打开手机的第一件事不是拨打电话，而是打开了类似QQ中常用的群组功能，查看着自己“好友们”的在线情况，并肆无忌惮地和在线的好友们瞎扯起来的话，千万不要认为这是运营商又在搞话费优惠活动，这一切完全是得益于一项为我们既熟悉但又陌生的技术——PTT（Pusn To Talk，简称PTT，意为“即按即说”）。展开更多
Poc（Push to Talk Over Cellular,无线一键通）技术是近段时间曝光率较高的新词汇，尤其伴随着摩托罗拉和索爱一些新机的发布，这项通过软件在手机上实现的新技术被描绘成可以让人们“像对讲机一样使用手机，并且只按一下键就可与另外...Poc（Push to Talk Over Cellular,无线一键通）技术是近段时间曝光率较高的新词汇，尤其伴随着摩托罗拉和索爱一些新机的发布，这项通过软件在手机上实现的新技术被描绘成可以让人们“像对讲机一样使用手机，并且只按一下键就可与另外一个用户或一组用户通话”。并且还具有通话费用低廉优点，被美国Zelos Group的调查报告认为是“未来新一代手机的两大热点”之一。事实也是如此，最明显的例子就是在本年度的3GSM展会上，讨论的热点不是来自3G。展开更多
采用内置天线滑盖设计的SGH-E350是一款定位中低端用户的机型，该机拥有仅75克的重量．配备了带闪光灯的30万像素VGA摄像头并支持MP3播放。相对三星过去推出的机型而言，E350比较独特的地方就是支持Push to Talk“一键通话”功能，可在...采用内置天线滑盖设计的SGH-E350是一款定位中低端用户的机型，该机拥有仅75克的重量．配备了带闪光灯的30万像素VGA摄像头并支持MP3播放。相对三星过去推出的机型而言，E350比较独特的地方就是支持Push to Talk“一键通话”功能，可在支持的网络中实现一对或一对多的半双工通话，展开更多
文摘For Push-To-Talk (PTT) system based on Public Mobile Data Network (PMDN), the end-to-end time delay is the key aspect of the user's experience. The Push-Over-Cellular (POC) scheme defined by Open Mobile Alliance (OMA) is based on the VoIP phone model and use SIP protocol as the call control scheme. The call setup time delay in SIP may reach to several seconds, which is unac-ceptable for the PTT service. In this paper, we provide a new call control scheme for PTT system based on PLMN network. By combining the apriority knowledge of PTT call model and the priority control scheme, we encapsulate the signaling message and the voice data into a same data packet, when the user push the button, the voice and the call control signaling are sent to the server at the same time. So the long time delay of call setup procedure of POC scheme can be eliminate. The end-to-end call delay can be decreased significantly. The experiment result based on the commercial CDMA2000 1X network of China Unicom shows that the call delay can be decreased to 600 ms, which approach to the traditional trunk communication system's requirement.
文摘“长江，长江，我是黄河，收到请回复。”……这个耳熟能详的电影对白如果随时随刻在我们身边出现，大家一定会觉得是对讲机发烧友们的恶作剧：再如果某天看到某人打开手机的第一件事不是拨打电话，而是打开了类似QQ中常用的群组功能，查看着自己“好友们”的在线情况，并肆无忌惮地和在线的好友们瞎扯起来的话，千万不要认为这是运营商又在搞话费优惠活动，这一切完全是得益于一项为我们既熟悉但又陌生的技术——PTT（Pusn To Talk，简称PTT，意为“即按即说”）。
文摘Poc（Push to Talk Over Cellular,无线一键通）技术是近段时间曝光率较高的新词汇，尤其伴随着摩托罗拉和索爱一些新机的发布，这项通过软件在手机上实现的新技术被描绘成可以让人们“像对讲机一样使用手机，并且只按一下键就可与另外一个用户或一组用户通话”。并且还具有通话费用低廉优点，被美国Zelos Group的调查报告认为是“未来新一代手机的两大热点”之一。事实也是如此，最明显的例子就是在本年度的3GSM展会上，讨论的热点不是来自3G。
