Bluetooth Capacity & Throughput
Original Post: Bluetooth Capacity & Throughput (SIG
Forum) Date: 2000-03-16
Bluetooth can support:
- an asynchronous data channel,
- up to three simultaneous synchronous voice channels, or
- a channel which simultaneously supports asynchronous data and
synchronous voice.
Each voice channel supports 64 kb/s synchronous
(voice) link in each direction. The asynchronous channel can support an
asymmetric link of maximally 723.2 kb/s in either direction while
permitting 57.6 kb/s in the return direction, or a 433.9 kb/s symmetric
link. See transmission speed table below.
Note: D stands for Data , M stands for Medium rate
, H stands for High rate
(All rates are in Kbits/sec)
| Packet Type |
Max Symmetric rate (two way) |
Max Forward (Assymetric) rate |
Max Reverse (Assymetric) rate |
| DM1 |
108.8 |
108.8 |
108.8 |
| DH1 |
172.8 |
172.8 |
172.8 |
| DM3 |
258.1 |
387.2 |
54.4 |
| DH3 |
390.4 |
585.6 |
86.4 |
| DM5 |
286.7 |
477.8 |
36.3 |
| DH5 |
433.9 |
723.2 |
57.6 |
| AUX1 |
185.6 |
185.6 |
185.6 |
Maximum number of active users on one piconet is 7
plus the master. Can have special 'parked' slaves - and many of them. In
countries where they use 79 hopping frequencies (USA and parts of Europe)
obviously there is a (basic) 1/79 chance that you will collide with
another piconet. An increased no. of piconets means an increased
chance of collisions.
Other countries only use 23, so 1/23 chance. You
must also be aware that there are some packets which span 5 times the
normal slot size, so the chances of this type of packet being involved in
a collision is higher. |
