Bluetooth Technology - Part 7

 

 

 

Bluetooth Introduction:

Bluetooth is a short-range wireless communication technology used for various applications. Bluetooth uses the Industrial, scientific and Medical band (ISM) which range from 2.402GHz to 2.48GHz. Bluetooth technology helps to build personal area networks (PAN). IEEE 802.15.1 is the standard defined by IEEE for Bluetooth. Bluetooth facilitates voice and data transmission by means of simple wireless connection. Bluetooth can form a connection between portable as well as between portable and stationary devices. Nordic Semiconductor, TI, Si Labs, Cypress Semiconductor, ST Microcontroller, Microchip, DIALOG is some of the major players in the Bluetooth Chipset market. Nordic Semiconductor has largest share of Bluetooth market. 

Bluetooth Versions:

 

Bluetooth Classic and Low Energy are similar but not compatible with one another. If a Bluetooth device must provide both modes, it must support dual mode.

Comparison between Bluetooth Classic and Bluetooth Low Energy:

Features	Bluetooth Classic	Bluetooth Low Energy
Application	Cell phones, headsets, stereo/audio streaming, automotive (hands free), PCs, etc.	Smartwatches, sport & fitness, home electronics, automation, industry, healthcare, smartphones, etc.
Voice	Yes	No
RF band ISM	2.4 GHz	2.4 GHz
Coverage	Depends on Transmit Power	Depends on Transmit Power
Power	3 classes (max.): +20 dBm, +4 dBm, 0 dBm	max. + 20 dBm
Connection	Inquiry (only connection based)	Advertising (connection based and connection less)
	Always hopping	Connection only if necessary, then hopping
Connection setup	100 ms Max. (Depends on Range and signal strength)	6 ms Max. . (Depends on Range and signal strength)
RF channels	79 with 1 MHz spacing	40 with 2 MHz spacing
Max.  data rate	3 Mbit/s	2 Mbit/s
Practical data rate	2.1 Mbit/s Max.	0.6 Mbit/s Max.
Indoor Locating	no	yes

 

• The most important feature of the BLE (Bluetooth Low Energy) is the low energy consumption.
• Low Power Consumption is achieved by a device being mostly inactive (99.9 % of the time). BLE applications require relatively low data rates.
• Bluetooth Low Energy is the designation for special extensions starting with Version 4.0.
• Bluetooth Versions 4.1 and 4.2 provide minor extensions/improvements over Version 4.0. This is the reason why same hardware exists but with a different software BT stack
• Version 5.0 and previous Versions have different hardware.
• Version 5.1 enables special Direction-Finding methods.
• BLE 5.0 has added BLE Mesh capabilityDual Mode Devices comprising of BLE + Classic options used for Audio are also available in the market

 Bluetooth Standards, Data Rate:

Standard	Data Rate	Example Chipsets
1.0 and 1.0B
1.1
1.2	721 Kbps	ABBTM-2.4GHZ-33-T
2.0 + EDR	2.1 Mbps	LMX9830SMX
2.1 + EDR	3 Mbps	BC63B239A04-AQK-E4
3.0	1Mbps	CYW20930A0KML2G
3.0 + EDR	3Mbps	CYW20733A3KFB1G
4.0	1 Mbps	CC2540
4.0 + EDR	3 Mbps	CYW20702B0KWFBG
4.1	< 2 Mbps	CSR1010
4.1 + EDR	3Mbps	CYW20704UA2KFFB1GT
4.2	< 2 Mbps	nRF51822, DA14681, Blue NRG - 1
5.0	2 Mbps	RA4W1
5.1	2 Mbps	CC2640R2F, Blue NRG - 2
5.2	2 Mbps	nRF52840, EFR32BG22

Note: 1.0,1.0B,1.1,1.2 standards are upgraded by 2.0

Interfacing to Microcontroller:

·         Bluetooth chips are available with inbuilt Microcontroller or as well as standalone chips

·         SPI is the most common interface used for interfacing the Microcontroller

Bluetooth Applications:

·         Bluetooth Speaker, headset

·         Smart watches connectivity to Mobile, transmitting the fitness information to Mobile

·      iBeacons to be used in Malls for tracking the items and indicating the closeness to the desired location in the mall

·         Smart Lightning

·         Digital Photo frame

·         Data Logging equipment based on Bluetooth

·         RS232 to Bluetooth converter

·         Game consoles like the play station (HID)

·         Bluetooth based printer, mouse

·         BLE Bluetooth Smart Accelerometer Beacon

·         Bluetooth Based Attendance system

·         Bluetooth Based Electric Rechargeable Power Toothbrush

·         Bluetooth in IoT Applications (Example: Connecting industrial appliances to a floor personal in the shop floor of Manufacturing)

·         In Agriculture embedded with sensors, Smart Agriculture

·         Tracking the assets using Bluetooth Temperature monitoring using Bluetooth

·         Bluetooth based webcam

·         Infotainment systems

·         Blood Pressure Monitor using Bluetooth

·         Home security system, Home Automation

Products with Bluetooth Chipsets:

·         CC2564 (BLE4.1 and Classis) is used in HID, SPP (Serial Port Profile), Fitbit Surge, Pebble Time

·         nRF51422 (BLE + ANT + GAZELL) is used in Misfit Flash Link

·         DA14580 is used by Xiaomi Mi

 Appendix:

BR = Basic Rate

EDR = Extended Data Rate

BLE = Bluetooth Low Energy

RSSI = Receive signal Strength Indication

ISM = Industrial, scientific and Medical band