什么叫蓝牙

什么叫蓝牙蓝牙是一种近距离的无线传输应用技术，在10 100米范围内，把专用的半导体装入机器中，无须借助电缆就可连接计算机、打印机、数字相机、电视机、手机、微波炉等，并能同时进行数据和语音传输。

是英语blue tooth的直译。

下面是小编为您收集整理的什么叫蓝牙，供大家参考!什么叫蓝牙What is Bluetooth?Bluetooth is a universal radio interface in the 2.45GHz frequency band that enables portable electronic devices to connect and communicate wirelessly via short-range, ad hoc networks. Each unit can simultaneously communicate with up to sever other units per piconet. Moreover, each unit can simultaneously belong to several piconets.What is Bluetooth Technology?Bluetooth technology which apart from Ericsson, has gained the support of Nokia, IBM, Toshiba, Intel and many other manufacturers.Eliminates the need for wires, cables and connectors for and between cordless or mobile phones, modems, headsets, PDAs, Computers, printers, projectors, local area networks, and so on, and paves the way for new and completely different devices and applications.Technology Characteristics 1Ms/s symbol rate exploits maximum available channel bandwidth.Fast frequency hopping avoids interferenceAdaptive output power minimizes interferenceShort data packets maximize capacity during interferenceFast acknowledge allows low coding overhead for linksCVSD(Continuous Variable Slope Delta Modulation)voice coding enables operation at high bit- error ratesFlexible packet types supports wide application rangeAir interface tailored to minimize current consumptionBasic Technical Information Based upon a small, high performance integrated radio transceiver, each of which is allocated a unique 48-bit address derived from the IEEE 802.standard.Operate in the unrestricted 2.45GHz ISM free band, Which is available globally although slight variation of location and width of band apply. Range set at 10m to optimize for target market of mobile and business userGross data rate 1Mbit/s with second generation plans to increase to 1Mbit/sOne-to-one connections allow maximum data transfer rate of 721kbit/s (3 voice channels)Uses packet switching protocol based on frequency hop scheme with 1600 hops/s to enable high performance in noisy radio environments. The entire available frequency spectrum is used with 79 hops of 1Mhz bandwidth, analogous to the IEEE 802.11 standard.Low power consumption longevity for battery powered devices. During data transfer the maximum current drain is 30mA. However during pauses or at lower data rates will be lower.蓝牙是一个频率为2.45GHz的通用无线电通信接口，它通过一个特殊的网络可以在各种便携设备之间建立起无线连接并进行短程通信。

在一个微微网中，每个单元都能同时与其它各单元进行通信。

而且，每一个单元可以同时属于几个微微网。

什么是蓝牙技术?蓝牙技术最先是由爱立信开始研制的，现在已经得到了诺基亚、IBM、东芝、因特尔及许多其它相关制造厂家的支持。

其目的是为了免除在无绳电话或移动电话、调制解调器、头套式送/受话器、PDAs、计算机、打印机、幻灯机、局域网等之间加装电线、电缆和连接器。

而且，这种技术可以延伸到那些完全不同的新设备和新应用中去。

蓝牙的技术特性以每秒1M个码元的字符速率传输，充分利用信道的最大有效带宽。

快速跳频避免干扰可变的电源输出使干扰减小到最小采用短数据包传输增强抗干扰能力快速确认允许有附加低速率的编码被发送到链路上连续可变斜率增量调制的语音编码可以在高误码率的情况下正常工作灵活的分组类型支持多种应用无线电空中接口使电耗达到最小蓝牙基本技术概要每一个小型、高性能、集成的无线电收发机都有IEEE 802标准所规定的一个唯一的48比特位地址开放的2.45GHz ISM自由频段，全球都可以自由使用。

10公里是最适于移动通信市场和商业用户的通信范围总速率为1Mbit/s，计划下一代产品将达到2Mbit/s点到点连接允许的最大数据传输速率为721kbit/s在无线电噪声环境里，利用基于每秒1600跳跳频表的分组交换协议可以提高系统性能。

以1Mhz带宽79跳来利用这个完整的可用频谱。

这类似于IEEE 802.11标准。

低电能的消耗。

在备用模式下仅需0.3mA，这能延长那些使用电池供电设备的寿命。

数据传送时电流的最大消耗为30mA.当暂停工作或低速传送数据时电流消耗更低。

数字钱包Digital WalletsA digital wallet is software that enables users to pay for goods on the Web. It holds credit-card numbers and other personal information such as a shipping address. Once entered, the data automatically populates order fields at merchant sites.When using a digital wallet, consumers don t need to fill out order forms on each site when they purchase an item because the information has already been stored and is automatically updated and entered into the order fields across merchant sites. Consumers also benefit when using digital walletsbecause their information is encrypted or protected by a private software code. And merchants benefit by receiving protection against fraud.Digital wallets are available to consumers free of charge, and they re fairly easy to obtain. For example, when a consumer makes a purchase at a merchant site that s set up to handle server-side digital wallets, he types his name and payment and shipping information into the merchant s own form. At the end of the purchase, one consumer is asked to sign up for a wallet of his choice by entering a user name and password for future purchases. Users can also acquire wallets at a wallet vendor s site. Although a wallet is free for consumers, vendors charge merchants for wallets.Digital wallets come in two main types: client-side and server- side. Within those divisions are wallets that work only on specific merchant sites and those that are merchant agnostic.Client-based digital wallets, the older of the two types, are falling by the wayside, according to analysts, because they require users to download and install software. A user downloads the wallet application and inputs payment and mailing information. At that point, the information is secured and encrypted on the user s hard drive. The user retains control of his credit card and personal information locally.With a server-based wallet, a user fills out his personal information, and a cookie is automatically downloaded. (A cookie is a text file that contains information about the user.)In this scenario, the consumer information resides on the server of a financial institution or a digital wallet vendor rather than on the user s PC.Server-side wallets provide assurance against merchant fraud because they use certificates to verify the identity of all parties. When a party makes a transaction, it presents its certificate to the other parties involved. A certificate is an attachment to an electronic message usedto verify the identity of the party and to provide the receiver with the means to encode a reply.Furthermore, the cardholder s sensitive data is typically housed at a financial institution, so there s an extra sense of security because financial environments generally provide the highest degree of security. But even though wallets provide easy shopping online, adoption hasn t been widespread.Standards are pivotal to the success of digital wallets.数字钱包是一种能使用户在Web网上支付货款的软件。