What Is Bluetooth Coexistence? (Answered)
Bluetooth is a well-known wireless technology that was designed decades ago, especially for short-range wireless connections between two devices within an area called Wireless Personal Area Network (WPAN). After a few years of its invention, many router broadband companies implied the phenomenon of “Bluetooth Co-existence” within their routers for the advancement of connectivity. How? Bluetooth will continue to exist along with the Wi-Fi services, featuring the optional name as Bluetooth Coexistence.
Bluetooth Coexistence With Wi-Fi:
Both of these wireless media—Bluetooth and Wi-Fi are quite similar. They might transmit in different ways. However, the protocols they use to do it are quite different. Whenever Wi-Fi is operating in the 2.4 GHz band, the transmission for Wi-Fi signals easily interferes with Bluetooth transmissions. The case is vice versa with the Bluetooth transmissions; they transmit to interfere with Wi-Fi transmissions similarly. Why so? It is because Bluetooth and Wi-Fi radio transmissions are often operated in a similar physical area and most of the time, in the same device. This is why the existence of both of these technologies have a profound effect on each other.
802.11 model is fully compatible with Wi-Fi technology connecting digital devices as well as infrastructure within a Wireless Local Area Network (WLAN). When it comes to compatibility, Bluetooth and Wi-Fi both tend to perform transmissions using distinct ways and multiple protocols. Why? Because Bluetooth and 802.11b, 802.11g, and 802.11n-compliant devices are capable to operate in the typical 2.4 GHz frequency band, and they always interfere mutually.
Moreover, both the Bluetooth and Wi-Fi radios’ operations take place within a similar physical area network and mostly in the same device. Remember that this type of interference has higher chances to affect the performance and stability of both these two wireless interfaces. There are several ways to mitigate network interference between those two media. This mitigation is done by temporal, ideal, and frequency isolation. If you want to look up these, you can search out the interference mitigation solutions.
Bluetooth Coexistence Option Of Wireless Routers:
Following the feature of Bluetooth coexistence with other wireless technologies in which Wi-Fi tops it all, some of the specific wireless routers have an isolated option of Bluetooth Coexistence, right under the wireless settings professional tab, specifically for the 2.4 GHz band.
Many users wonder about what this option is used for. By now, you must have a fair idea of how the Bluetooth Coexistence phenomenal feature works. This is exactly why this option has been made.
Some of the routers have the following three settings for the Bluetooth Coexistence option.
An 802.11 device easily interferes with Bluetooth devices operating on the 2.4 GHz band. Almost every Bluetooth device operates at the 2.4 GHz band. Whenever you experience frequent wireless disconnects, less space or range for network coverage or stunt speeds, or any other connectivity issue, all you would have to do is to turn on some of your Bluetooth devices and switch the option to “Enable”. Doing so would cause your router and Bluetooth device to take turns in using the produced spectrum for communication or simply for “Preemption”.
However, you will need to make sure that this option is cooperated with your Bluetooth device and Wi-Fi router to truly experience the phenomenon of Bluetooth Coexistence.
BLUETOOTH TECHNOLOGY Coexistence Of Bluetooth And Wi-Fi
Presentation on theme: «BLUETOOTH TECHNOLOGY Coexistence Of Bluetooth And Wi-Fi»— Presentation transcript:
1 BLUETOOTH TECHNOLOGY Coexistence Of Bluetooth And Wi-Fi
Presented by: JIGAR A. SHAH K.K. Wagh College of Engg. YUGA SOMVANSHI
3 Overview of Wi-Fi (802.11b) It is specification for WLAN
Wireless Ethernet Compatibility Alliance certify product as Wi-Fi compatible Data transmission on BPSK and QPSK Data transmission at 11 Mbps Direct Sequence Spread Spectrum (DSSS) Devices are classified as Access Point and Station Range of data transmission up to 100m
4 Frequency occupancy of three Wi-Fi Networks
5 Overview of Bluetooth It is WPAN technology Data transmission on GFSK
Hops at 1600Hz over 79 channels of 1MHz Uses Frequency Hopping Spread Spectrum (FHSS) Devices are classified as Master and Slave Generally used as cable replacement technology Communication range up to 10m Data transmission at 724Kbps
6 Bluetooth frequency occupancy example
7 What is coexistence ? “Coexistence”, the ability for multiple protocols to operate in the same frequency band without significant degradation to either’s operation 2.4GHz ISM band is 83.5MHz wide with lower limit from 2.400GHz and higher limit from GHz Both Bluetooth and Wi-Fi utilizes same 2.4GHz ISM band Bluetooth device hops over 79MHz channel and Wi-Fi requires 16MHz bandwidth – chances of interference are very high Wi-Fi and Bluetooth are complementary rather than competing
10 Wi-Fi throughput – baseline performance
11 Bluetooth throughput — baseline
12 Wi-Fi performance with Bluetooth interference – Testing setup
Test -1 with Bluetooth Test – 2 with Bluetooth at 10m
13 Wi-Fi performance with Bluetooth interference
14 Bluetooth performance with Wi-Fi interference
15 Methods for Improved Coexistence
MAC layer switching Adaptive Fragmentation for Wi-Fi Networks Transmit Power control Dynamic Channel Selection for Wi-Fi Network Adaptive Frequency Hopping for Bluetooth Networks
16 FCC Regulations for transmitting power
Section of FCC regulation specifies high power transmission for FHSS and DSSS Section a of FCC regulations limits high power transmitters up to 1 Watt for DSSS and FHSS Minimum No. of channel to be hopped was 75 in 2002 To limit transmission power FCC changed min. number of channel to be hopped to 20 channels
17 Factors on which determination of best channel depends:
Packet error rate Channel noise Channel multipath and intersymbol interference Received signal strength
18 Wi-Fi and Bluetooth Interference
19 Adaptive Frequency Hopping (AFH) Example
20 AFH (Adaptive Frequency Hopping)
21 Changes in Bluetooth 1.2 specification
AFH is specified in Bluetooth 1.2 specification Base band: Updated base band describes the algorithm used for generating an adapted hop channel set LMP (Link Manger Protocol): it is updated with new message for communicating the bit mask that identifies which channel may be used and which are to be avoided The bit mask consist of 79 bits which gives detail about which channel is to be used and unused HCI (Host Controller Interface): it includes two new commands ; First to exclude channels from list Second one to read channel map currently in use
22 Limitation of AFH Not suitable for collocated Wi-Fi and Bluetooth devices, Effectiveness depends on antenna isolation, transmit power of devices and the sensitivity of receiver Requires antenna isolation Cannot be used if either master or slave does not support it Not effective for Bluetooth 1.1 compatible devices change
23 AFH is used with other coexistence technology
UltimateBlue™ by siliconwave Intel Wireless Coexistence System (WCS) Blue802™ technology
24 Coexistence Technique Comparison by Design Parameters
25 Standardization Activities
IEEE WPAN has formed different task groups: TG1 ( ) : reformulating BT 1.x spec into IEEE standards TG2 ( ) : Recommend practices coexistence of wireless devices operating in the 2.4GHz band Bluetooth SIG coexistence Working Group is established to make changes in Bluetooth standards
26 References Andrew Tanenbaum: Computer networks, fourth edition
Douglas Comer: Computer Networks and Internet Jennifer Bray, Charles Struman: Bluetooth-connect without cable
27 Web — References www.ti.com/wlan (Texas Instrument) www.wimaxforum.com