STA2500DTR STMICROELECTRONICS [STMicroelectronics], STA2500DTR Datasheet - Page 38

• Manufacturer Part Number: STA2500DTR
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

General specification
6.13
6.13.1
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Bluetooth - WLAN coexistence in collocated scenario
The coexistence interface uses up to 4 WLAN control signal pins, which can be mapped via
software parameter download on different pins of the STA2500D (see
The functionality of the 4 WLAN control signal pins depends on the selected algorithm, as
explained
below and summarized in
Bluetooth and WLAN 802.11 b/g [] [] technologies occupy the same 2.4 GHz ISM band. The
STA2500D implements a set of mechanisms to avoid interference in a collocated scenario.
The STA2500D supports 5 different algorithms in order to provide efficient and flexible
simultaneous functionality between the two technologies in collocated scenarios:
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The algorithm is selected via an HCI command. The default algorithm is algorithm 1.
Algorithm 1: PTA (packet traffic arbitration)
The algorithm is based on a bus connection between the STA2500D and the WLAN chip:
Figure 13. PTA diagram
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
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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. ST specific HCI commands are implemented to select the
algorithm and to tune the priority handling.
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 STA2500D when not to
operate in case of simultaneous use of the air interface.
Algorithm 3: the STA2500D 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.
a priority mechanism, which allows preserving the quality of certain types of link.
a mechanism to indicate that a periodic communication is ongoing.
STLC2500D
Table
Doc ID 16067 Rev 1
25.
RF_REQUEST
RF _ CONFIRM
STATUS
FREQ
WLAN
Section
7.5).
STA2500D