| 1. | Technical requirment and test method for digital queue equipment of pstn
公用电话网数字排队机技术要求及测试方法 |
| 2. | Technical requirements and test methods for interface between non - voice subscriber terminal and public telephone network
非话用户终端设备与公用电话网接口技术要求和测试方法 |
| 3. | This system regards pstn as communication channels and realizes data long - distance transmitting , saving and processing
本系统以公用电话网作为通信信道，实现水情数据的远距离传输、存储和处理。 |
| 4. | But , transmission rates over pstn and wireless networks are still limited . futhermore , pstn and wireless networks are error prone environment
但是，公用电话网和无线网络的带宽是及其有限的，而且这些线路上极其容易发生错误。 |
| 5. | The upper computer that connected with modem via rs - 232 , and the modem connected with the public telephone network in the monitoring center communicated with the distant controller
上位机通过rs - 232与modem相连接入公用电话网，实现对单片机控制器的遥测、遥控。 |
| 6. | In addition ， manufacture a modem based on pc104 bus embedded computer system ' s rs232 serial port . the pc104 bus embedded computer system may communicate with manager computer through modem and public phone net
如果，上述pc104总线嵌入式计算机系统中的监控软件有与远方的上位机通信的要求，那么，可通过此调制解调器借助公用电话网实现 |
| 7. | But owing to the now available structure of public telephone net at present , such as the raw and processed material of copper hawser reduces gradually , his price is more and more expansive , and result in the cost of providing service increased
作为公用电话网，其发展速度也是十分惊人的。然而，由于目前公用电话网的现有结构，如铜缆的原材料逐渐减少，其价格越来越昂贵，使得提供服务的成本增加。 |
| 8. | With the fast development of pstn and mobile telephone , a demand for image communication increases rapidly . meanwhile , the wide use of internet promotes the use of video mail , remote medical treatment , remote education and shopping through the net
随着公用电话网的普及以及蜂窝移动通信的发展，人们对于可视电话的需求与日俱增；同时pc机和internet的广泛使用也进一步促进了视频邮件、网上购物、远程教育以及远程医疗的应用。 |
| 9. | Through calling various function of the mscomm activex control provided by vb to realize serial - parallel communication and programming the modem . it can realize the function of establishing data link circuit and gathering the electrical parameters of transformer by pstn and so on
本文通过对vb提供的用于串行通信的mscomm控件所提供的各种功能的调用以及对modem编程，实现了从数据链路的建立到通过公用电话网对变压器电量数据采集等多项功能。 |
| 10. | With the development of human ' s living level , the demand for digital video communication such as video conferencing , video e - mailing and video telephonv has increased considerably so that these digital signal should be transmitted over the public switched telephone networks ( pstn ) or wireless networks
随着人们生活水平的提高，视频会议，视频电子邮件，可视电话等数字视频通信应用需求的增加，越来越需要在公用电话网( pstn )或无线网络中传输视频数字信号。 |
