STLC2500A View Datasheet(PDF) - STMicroelectronics
Part Name
Description
MFG CO.
'STLC2500A' PDF : 37 Pages View PDF
STLC2500A
General specification
Examples of parameters are: radio configuration, PCM settings etc.
The same HCI command is used to download the file containing the patches (both those for
the SW and HW mechanism).
A more detailed description of the SW parameters is available upon request.
6.11
6.11.1
Bluetooth - WLAN coexistence in collocated scenario
The coexistence interface uses up to 4 GPIO pins, the unused ones can be used as GPIOs.
Bluetooth and WLAN 802.11 b/g technologies occupy the same 2.4 GHz ISM band.
STLC2500A implements a set of mechanisms to avoid interference in a collocated scenario.
The STLC2500A supports 5 different algorithms in order to provide efficient and flexible
simultaneous functionality between the two technologies in collocated scenarios:
– Algorithm 1: PTA (Packet Traffic Arbitration) based coexistence algorithm defined
in accordance with the IEEE 802.15.2 recommended practice.
– Algorithm 2: the WLAN is the master and it indicates to the STLC2500A when not
to operate in case of simultaneous use of the air interface.
– Algorithm 3: the STLC2500A is the master and it indicates to the WLAN chip
when not to operate in case of simultaneous use of the air interface.
– Algorithm 4: Two-wire mechanism
– Algorithm 5: Alternating Wireless Medium Access (AWMA), defined in
accordance with the WLAN 802.11 b/g technologies.
The algorithm is selected via HCI command. The default algorithm is algorithm 1.
Algorithm 1: PTA (Packet Traffic Arbitration)
The Algorithm is based on a bus connection between the STLC2500A and the WLAN chip.
Figure 7. Bus connection between STLC2500A and WLAN chip
STLC2500
WLAN
By using this coexistence interface it is possible to dynamically allocate bandwidth to the two
devices when simultaneous operations are required while the full bandwidth can be
allocated to one of them in case the other one does not require activity. The algorithm
involves a priority mechanism, which allows preserving the quality of certain types of link. A
typical application would be to guarantee optimal quality to the Bluetooth voice
communication while an intensive WLAN communication is ongoing.
Several algorithms have been implemented in order to provide a maximum of flexibility and
efficiency for the priority handling. Those algorithms can be activated via specific HCI
commands.
The combination of a time division multiplexing techniques to share the bandwidth in case of
simultaneous operations and of the priority mechanism avoid the interference due to packet
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