Introduction
Bluetooth is a wireless communication technology (without cable) that operate in the frequency band 2.4 GHz unlicensed ISM (Industrial, Scientific and Medical) using a frequency hopping tranceiver is capable of providing service data and voice communication in real-time between the hosts bluetooth distance service with a limited (about 10 meters). Bluetooth itself may be cards that form and function with almost the same card used for wireless local area network (WLAN) use radio frequencies where the IEEE 802.11 standard, only the bluetooth range distance service has a shorter data transfer capability and a lower.
Basically, Microsoft created not only to replace or eliminate the use of the cable to the exchange of information, but also able to offer a good feature for mobile wireless technology with a relatively low cost, low power consumption, interoperability promising, easy in operation and able to provide services the manifold. To give a clearer picture of the bluetooth technology is relatively new to this reader, the following are described on the history of the emergence and growth of Bluetooth, the technology used in the system and the bluetooth service is provided that is capable of, and a little description about the comparison of modulation methods of spread spectrum FHSS (Frequency Hopping Spread Spectrum) used by the bluetooth method compared with the spread spectrum DSSS (Direct Sequence Spread Spectrum).

Bluetooth Background
In May 1998, the 5 promoter company Ericsson, IBM, Intel, Nokia and Toshiba established a Special Interest Group (SIG) and start to create specifications that they Rename 'bluetooth'. In July 1999 a document bluetooth specification version 1.0 was launched start. In December 1999 started making the document more bluetooth specification version 2.0 with additional 4 new promoter that is 3COM, Lucent Technologies, Microsoft and Motorola. Currently, more than 1800 companies in various fields, among others in the field of Semiconductor Manufacture, Manufacture PC, mobile network carriers, automobile companies and water lines bergambung in the consortium as a technology adopter bluetooth. Leading companies, among others such as Compaq, Xircom, Phillips, Texas instruments, Sony, BMW, Puma, NEC, Casio, Boeing, etc..
Although the standard Bluetooth SIG currently 'owned' by a group promoter, but he is expected to become an IEEE standard (802.15).

Applications and Services
Bluetooth protocol uses a combination of circuit switching and packet switching. Bluetooth can support a channel data asinkron, three-channel simultaneous voice or a sync channel which simultaneously supports data services asinkron and sound sync. Each voice channel supports a voice channel synchronized 64 kb / s. Asinkron can support channel speeds up to 723.2 kb / s asymmetric, where the direction to be able to support speeds up to 57.6 kb / s. While for the symmetric mode can support speeds up to 433.9 kb / s.
A device that has Bluetooth wireless technology will have the ability to conduct information exchange with the distance range up to 10 meters (~ 30 feet). Bluetooth system provides point to point communication and point to multipoint communication.

Bluetooth product can be a PC card or USB adapter that is inserted in the device. Devices that can diintegerasikan with bluetooth technology including: mobile PC, mobile phone, PDA (Personal Digital Assistant), headset, camera, printer, router, and so forth. Applications that can be provided by the bluetooth services include: PC to PC file transfer, PC to PC synch file (notebook to desktop), PC to mobile phone, PC to PDA, wireless headsets, LAN connection via ethernet access point, and so forth .

Figure 1 and 2 are examples of some of the modules and applications bluetooth.

General Diskripi Bluetooth System
The system consists of a Bluetooth radio transceiver, baseband link controller and a link manager. Baseband link controller hardware connecting the radio to the base band processing and physical layer protocols. Link managers perform activities such as high-level protocol to link setup, authentication and configuration. In general, the functional blocks in the Bluetooth system can be seen in Figure 3.
Radio Characteristics
Here are some karaketristik bluetooth radio in accordance with the Bluetooth SIG documents be in Table 1.

Parameter Specification
Transmitter:
ISM frequency band, 2400 - 2483.5 MHz (the majority), for some countries have their own frequency limits (see table 2), space channel 1 MHz.
Maximum Power Output Power class 1: 100 MW (20 dBm) Power class 2: 2.5 MW (4 dBm) Power class 3: 1 MW (0 dBm)
GFSK modulation (Gaussian Frequency Shift Keying), Time Bandwidth: 0.5; Modulation Index: 0:28 until 0:35.
Out of band Spurious Emission 30 MHz - 1 GHz: -36 dBm (operation mode), -57 dBm (idle mode) 1 GHz - 12.75 GHz: -30 dBm (operation mode), -47 dBm (idle mode) 1.8 GHz -- 1.9 GHz: -47 dBm (operation mode), -47 dBm (idle mode) 5.15 GHz -5.3 GHz: -47 dBm (operation mode), -47 dBm (idle mode)
Receiver:
Actual Sensitivity Level -70 dBm at 0.1% Ber.
Spurious Emission 30 MHz - 1 GHz: -57 dBm1 GHz - 12.75 GHz: -47 dBm
Max. usable level of -20 dBm, Ber: 0.1%

Frequency band and RF channels
Bluetooth operates in the frequency band 2.4 GHz ISM, although the global allocation of frequencies has bluetooth, but for many countries the allocation of appropriate frequency and wide band frequency that is used is different. Limit the frequency and the RF channel used by some countries can be seen in Table 2.

Country Channel RF Frequency Range
* Europe) and USA 2400 - 2483.5 MHz f = 2402 + k MHz k = 0, ..., 78
Japan 2471 - 2497 MHz f = 2473 + k MHz k = 0, ..., 22
Spain 2445 - 2475 MHz f = 2449 + k MHz k = 0, ..., 22
France 2446.5 - 2483.5 MHz f = 2454 + k MHz k = 0, ..., 22

*) Except for Spain and France
Time Slot
Channel is divided in time-slot time slot, each have a length of 625 ms. Time-slot time slot be numbered in accordance with the master clock of the piconet bluetooth. Delivery slot numbering from 0 to 227-1 with a cycle length of 227. In the time slot, the master and slave can transmit packets using the scheme with TDD (Time Division-duplex), see figure 4. Master pentransmisiannya only start doing a number on the whole time slot while slave only just started doing pentransmisiannya time slot on the odd numbers only.
Bluetooth protocol
Bluetooth protocols are intended to accelerate the development of applications using bluetooth technology. Layer-layer on the bottom of the Bluetooth protocol stack is designed to provide a basis for the development of a flexible protocol that further. Protocols such as RFCOMM is taken from the protocols that already exist and the protocol is only slightly modified for compliance with the interests of bluetooth. On the protocols used on the layer without making modifications. Thus, applications that already exist can be used with bluetooth technology so that interoperability will be assured.
Bluetooth protocol stack can be divided into four layers according to the purpose. Following the protocols in the layer-layer in the bluetooth protocol stack shown in Table 3 and Figure 5.

Table 3. Protocols, and layer-layer in the bluetooth protocol stack (source: Bluetooth SIG)

Protocol Layer Protocols in the stack
Bluetooth Core Protocols Baseband, LMP, L2CAP, SDP
Cable Replacement Protocol RFCOMM
Telephony Control Protocols TCS Binary, AT-commands
Adopted Protocols PPP, UDP / TCP / IP, OBEX, WAP, vCard, vCal, IrMC, Wae

A more detailed description of the bluetooth protocol, will not described in this paper.

Measurement Bluetooth
Basically there are three important aspects of making measurements in the measurement of the bluetooth RF (Radio Frequency), protocol and profile. Radio measurements made to provide compatibility radio device that is used in the system and to determine the quality of the system. Measurement radio can use the tool as a standard measure RF spectrum analyzer, transmitter analyzer, power meter, digital signal generator and bit-error-rate tester (Bert). Measurement results must be in accordance with the specifications that have been defined in one must meet the parameters listed in Table 1.
Information from the Test & Measurement World, for the measurement protocol, you can use a protocol sniffer that can monitor and display the movement of data between bluetooth devices. In addition, the device can use the Ericsson Bluetooth Development Kit (EBDK). Ericsson akan segera merelease a EBDK version known as the Blue Unit.

Profile measurement is done to ensure interoperability between devices from various vendors. Structure profile in accordance with the bluetooth SIG document can be seen in Figure 6.

Example:

LAN access profile defines how Bluetooth devices are able to access services on a LAN using the Point to Point Protocol (PPP). In addition, this profile shows how the same PPP mechanisms are used to form a network that consists of two bluetooth devices.
Fax profile specify requirements bluetooth device that must be met to be able to support fax service. This allows a bluetooth cellular phone (modem) can be used by a computer as a wireless fax modem to send or receive a fax message. Besides the above three aspects, namely radio, protocol, then actually there's another aspect that is not less important for measurements to be performed on the measurement of the Electromagnetic Compatibility (EMC) which could refer to the European standard ETS 300 8 26 United States or the FCC standard Part 15.
Function Security
Bluetooth is designed to have security features that can be used safely both in the business environment and the home. Features provided by Microsoft, among others, as follows:
Data encryption.
User authentication
Fast frequency-hopping (1600 hops / sec)
Output power control
These features provide the security functions of the security level of the physical layer / radio interference from the tapping to the level of security to a higher layer such as a password and PIN.
Bluetooth FHSS vs. DSSS WLAN
Actually prefer the bluetooth method FHSS (Frequency Hopping Spread Spectrum) compared with DSSS (Direct Sequence Spread Spectrum). Reason why Microsoft does not make use of DSSS as follows:
1. FHSS requires power consumption and complexity is lower than DSSS this is because using DSSS chip rate (chip rate) compared with the speed symbol (symbol rate) used by the FHSS, so that the cost required to use DSSS akan higher.

2. FHSS uses FSK where resilience against interference noise is relatively better compared to the DSSS usually use QPSK (for the IEEE 802.11 2 Mbps) or CCK (IEEE 802.11b 11 Mbps).

Although FHSS have the distance range and data transfer that is lower than the DSSS but for the service under 2 Mbps FHSS can provide cost-effective solution that better.

Conclusion
Some explanation of the above, that Microsoft is able to offer solutions that are quite effective and efficient in providing services to the user to perform data transfer at speeds of less than 1 Mbit / s and the relatively short range. Bluetooth technology is still possible to continue to grow toward maturity both in the standardization and applications that can be applied. With bluetooth bahwasannya able to provide a wide range of applications and services and the cost is relatively cheap, easy in operation, that promise interoperability and supported by many major vendors in the field of telecommunications and computers, and more than 1800 companies have joined as a technology adopter, the not impossible when a bluetooth technology will be one of the excellent to good use for the purpose of household or office / business.
With little expected that this paper provides a description of the new bluetooth tekonologi to readers and can provide or add a new insight to the development of wireless communication.

References
Bluetooth Special Interest Group, Baseband Specification.
Bluetooth Special Interest Group, Radio Specification.
Bluetooth Special Interest Group, Bluetooth Protocol Arsitechture.
Bluetooth Special Interest Group, Bluetooth Security Arsitechture.
Angus Robinson, Anritsu, Stevenage, UK, On Your Marks for Bluetooth Testing, Test & Measurement Worls, September 2000
ETS 300 328, Radio Equipment and Systems (Res); Wideband transmission systems; Technical Characteristics and test conditions for data transmission equipment operating in the 2.4 GHz band and using spread spectrum techniques Modulation.
ETS 300 826, Electromagnetic compatibility and radio spectrum matters (ERM), ElectroMagnetic Compatibility (EMC) standard for 2.4 GHz wideband transmission systems and High Performance Radio Local Area Network (HIPERLAN) equipment. 8. Bluetooth Presentation, Business Div Bluetooth, Digital Media Network Company, Toshiba Corporation, 2000.
Jim Geier, Spread Spectrum: Frequency Hopping vs.. Direct Sequence, May 1999.
Http: / / www.motorola.com / bluetooth
Http: / / www.cetecom.com / bluetooth
Http: / / www.palowireless.com
Bluetooth Special Interest Group, the Serial Port Profile.
Tri Susanto, laboratory Quality Engineer in the Security-Reliability RisTI, TELKOM