1. Improving Bluetooth EDR Data Throughput Using FEC and Interleaving
Ling-Jyh Chen*, Tony Sun**, Yung-Chih Chen*
*Institute of Information Science, Academia Sinica
**Dept. of Computer Science, UCLA

2. Introduction
Wireless communication is inherently vulnerable to errors.
Wireless channel errors are usually bursty and dependent in occurrences rather than independently/ identically distributed.
Some robust link layer transmission schemes are required.

3. Contribution
We propose three link layer enhancements for Bluetooth v2.0
Adaptive Packet Type (APT)
FEC coding
Interleaving FEC (IFEC)
The proposed solutions are applicable to other wireless technologies.

4. Outline Bluetooth Overview Proposed Link Layer Enhancements
Simulation Results
Conclusion

5. Asymmetric Throughput (kbps)
Bluetooth Overview
The “enabler” of Personal Area Network (PAN)
Low power, low cost, and smaller chips
Mode
FEC
Packet
Asymmetric Throughput (kbps)
Size (bytes)
Length (slots)
DM1
yes 17 1
108.8
DM3
121 3
387.2
54.4
DM5
227 5
477.8
36.3
DH1 no 27
172.8
DH3
183
585.6
86.4
DH5
339
723.2
57.6

6. Bluetooth packet types
DH: Stop and Wait ARQ
DM: ARQ as well as FEC codes
FEC coding scheme:
(15, 10) Shortened Hamming code
Able to correct single bit error in each block.

7. Bluetooth Enhanced Data Rate (EDR)
EDR does not provide FEC enabled packet types (ie., no DM series types)

8. Proposed Link Layer Enhancements
Adaptive Packet Type (APT)
FEC coding
Interleaving FEC (IFEC)

9. Enhancement (I): APT Adaptive Packet Type (APT)
Determine optimal packet type
T: Theoretical Data throughput
s: packet size/bits b: bit error rate p: packet error rate
n: packet length in Bluetooth slots

10. Enhancement (I): APT (Con’t)

11. Enhancement (II) : FEC Propose to apply FEC to Bluetooth EDR
Called 2DM1/3/5 & 3DM1/3/5
(15,10) shortened Hamming code that is able to correct single bit error
Packet Error Rate :
( p: packet error rate, b: bit error rate s: packet size/bits )

12. Enhancement (II) : FEC (Con’t)

13. Enhancement (III) – IFEC
Wireless errors are mostly bursty in presence, previous techniques should be modified.
Propose Interleaved FEC (IFEC) coding
Called DMI 1/3/5, 2DMI 1/3/5, and 3DMI 1/3/5
Burst Error Model (aka Gilbert-Elliott model)

14. Enhancement (III) – IFEC (Con’t)
FEC coding
Interleaved FEC coding

15. Simulation Results
Gilbert-Elliott model: Pgb= 0.005, Pbb from 0.9 to
FEC coding
IFEC coding

16. Conclusion
We proposed three link layer enhancement techniques (APT/FEC/IFEC) for BT EDR.
We verified the proposed techniques using simulation.
The proposed solutions are applicable to other wireless technologies.

17. Thank you !