Symbian OS 及通讯技术术语全解

核心提示：mobile phone system and the de facto wireless telephone standard in Europe. Originally defined as a pan-European open standard for a digital cellular telephone

mobile phone system and the de facto wireless telephone standard in Europe. Originally defined as a pan-European open standard for a digital cellular telephone network to support voice, data, text messaging and cross-border roaming. GSM is now one of the world's main 2G digital wireless standards. GSM is present in more than 160 countries and according to the GSM Association, accounts for approximately 70 percent of the total digital cellular wireless market. GSM is a time division multiplex (TDM) system. Implemented on 800, 900, 1800 and 1900 MHz frequency bands.

全球移动通信系统，使用最广泛的数字手机系统和欧洲事实上的无线电话标准。最初定义为数字蜂窝电话网络的泛欧洲开放式标准，用来支持语音、数据、文本消息和过境漫游。GSM 现在是世界上主要的2G 数字无线标准之一。GSM 存在于160 多个国家中，按照GSM 协会的数字，它约占整个数字蜂窝无线市场的70%。GSM 是一种时分多址(TDM) 系统。它在800、900、1800 和1900MHz 波段实现。

IrDA

1. A suite of protocols for infrared (IR) exchange of data between two devices, up to 1 or 2 meters apart (20 to 30 cm for low-power devices). IrDA devices typically have throughput of up to either 115.2 Kbps or 4 Mbps. IrDA protocols are implemented in Symbian OS phones, many PDAs, printers and laptop computers.

2. The Infrared Data Association, the industry body that specifies IrDA protocols, originally founded by Hewlett-Packard and others.

"1. 一套用来在距离达到1 或2 米(对于低功率设备为20 到30 厘米)的两个设备之间交换数据的红外(IR) 协议。IrDA设备的吞吐率通常可以达到115.2Kbps 或4Mbps。IrDA 协议由Symbian 操作系统手机、许多PDA、打印机和膝上型计算机实现。

2. 红外数据同盟，用来指定IrDA 协议的业内机构，最初是由Hewlett-Packard 和其他公司成立的。"

Java

Industry standard object-oriented language and virtual machine, invented by Sun Microsystems and formally released in 1996. Java is an ideal language for network applications and applets. Sun's Java specifications include many Java