HandsFree Profile (HFP)

2009. 07. 21

통신연구소 S/W Team 이상제

Table of contents

Configuration and Roles2

Application layer(HFP)6

Preface31

Protocol Stack33

Headset Profile35

ACL link and SCO link4

• What is Profile?– Describe how implementations of user models are to be

accomplished.– Decrease the risk of interoperability problems between

different manufacturers' products.

Preface

Preface

• What is HFP?– Defines the minimum

set of functions such that a Mobile Phone can be used in conjunction with a Hands-Free device

– Remote control of the Mobile Phone by the Hands-Free device

– Voice connections between the Mobile Phone and the Hands-Free device.

Configuration and Roles

• Audio Gateway (AG)– Gateway of the audio, both for input and output.

• Hands-Free unit (HF)– Acting as the Audio Gateway’s remote audio input and

output mechanism. It also provides some remote control means.

Protocol Stack

OSI Physical layer and Data link layer Bluetooth protocols.

Protocol Stack

RFCOMM is the Bluetooth serial port emulation entity

Protocol Stack

Bluetooth Service Discovery Protocol

Protocol Stack

Responsible for Hands-Free unit specific control signaling; this signaling is AT command based.

Protocol Stack

• SCO (Synchronous Connection Oriented)– Point-to-point link between the master and a specific

slave– Typically supports time-bounded information like voice

• ACL (Asynchronous Connectionless)– point-to-multipoint link between the master and all the

slaves participating on the piconet– Both asynchronous and isochronous services are

supported

SCO link and ACL link

Hands Free Profile

• What is deferent of HFP and HSP

Headset Profile

Headset Profile

<HSP Application layer>

Application layer(HFP)

Application layer(HFP)

• Service Level Connection establishment– Pre-condition: RFCOMM connection establishment – Service Level Connection Initialization – Link Loss Recovery

• Service Level Connection release– Pre-condition: Established Service Level Connection

Application layer

Feature HF AG

1. Connection Management M M

Service Level Connection establishment

Application layer

The HF notifies the AG about its own supported

features and

the AG responds with its supported features

Service Level Connection establishment

Application layer

The HF retrieves the information

describing the indicators supported in the AG

Service Level Connection establishment

Application layer

The HF requests the current status of

the indicators in the AG

Service Level Connection establishment

Application layer

The HF requests enabling Indicator Status

update in the AG

Service Level Connection establishment

Application layer

The HF retrieves the information

describing the call hold and

multiparty services supported in the AG

At least the two indicators “service” and “call”.

Application layer

Feature HF AG

2. Phone status information M M

Statusinformation

Signal Strength IndicationRegistration Status

Roaming Status Indication

Query Operator Selection

Report ExtendedAudio Gateway Error Results Code

Transfer of Call, Call Setup ,Held Call Status

Battery Level Indication of AG

• Audio Connection set up– Pre-condition: Established Service Level Connection– HF or the AG initiate the establishment of an Audio

Connection.– Always Synchronous Connection

• Audio Connection release– Pre-condition: Established Audio Connection – Disconnection of its corresponding Synchronous

Connection. – When the audio connection is released, the audio path

shall be routed to the AG.

Application layer

Feature HF AG

3. Audio Connection handling M M

• Answer an incoming call– Answer Incoming Call from the HF – In-Band Ringing

• Pre-condition : Established Service Level Connection

– Answer Incoming Call from the HF – No In-Band Ringing • Pre-condition : Established Service Level Connection

(or optionally an Audio Connection)

– Answer Incoming Call from the AG • Pre-condition : AG is alerting the HF

– Change the In-Band Ring Tone Setting • Pre-condition : Established Service Level Connection

Application layer

Feature HF AG

4. Accept an incoming voice call M M

Application layer

Feature HF AG

4. Accept an incoming voice call M M

Answer an incoming call from the HF – in-band ring tone

Answer an incoming call from the HF – no in-band ring tone

• Reject an incoming call– Reject an Incoming Call from the HF

• Pre-condition : AG is alerting the HF

– Rejection/Interruption of an Incoming Call in the AG • Pre-condition : AG is alerting the HF

Application layer

Feature HF AG

5. Reject an incoming voice call M O

• Terminate a Call Process from the HF– Pre-condition

• Established Service Level Connection• Ongoing call process

• Terminate a Call Process from the AG – Pre-condition

• Established Service Level Connection• Ongoing call process

Application layer

Feature HF AG

6. Terminate a call M M

• Audio Connection transfer towards the HF– Pre-condition

• Established Service Level Connection• The audio paths of the ongoing call are available at the AG

• Audio Connection transfer towards the AG– Pre-condition

• Established Service Level Connection• Ongoing call process with the audio paths routed towards

the HF

Application layer

Feature HF AG

7. Audio Connection transfer during an ongoing call

M M

AG

HF

HFAG

• Place a call with a phone number supplied by the HF– Pre-condition

• Established Service Level Connection(or optionally an Audio Connection)

• The audio paths of the ongoing call are available at the HF

- Initiate outgoing voice calls by providing the destination phone number to the AG.

Application layer

Feature HF AG

8. Place a call with a phone number supplied by the HF

O M

• Memory Dialing from the HF – Pre-condition : Established Service Level Connection

(or optionally an Audio Connection)– Initiate outgoing voice calls using the memory dialing

feature of the AG

Application layer

Feature HF AG

9. Place a call using memory dialing O M

• Last Number Re-Dial from the HF – Pre-condition : Established Service Level Connection

(or optionally an Audio Connection)– initiate outgoing voice calls by recalling the last number

dialed by the AG.

Application layer

Feature HF AG

10. Place a call to the last number dialed O M

• Call Waiting Notification Activation – Pre-condition

• Established Service Level Connection• Internal event or user requested: Enable Call Waiting

notification

– The HF requests enabling Call Waiting notification indication

Application layer

Feature HF AG

11. Call waiting notification O M

• Call Waiting Notification

Application layer

Feature HF AG

12. Three way calling O O

0 = Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.1 = Releases all active calls (if any exist) and accepts the other (held or waiting) call.2 = Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.3 = Adds a held call to the conversation.4 = Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer). Support for this value and its associated functionality is optional for the HF.

• Third Party Call Placed from the HF

Application layer

Feature HF AG

12. Three way calling O O

• Calling Line Identification (CLI) Notification – Pre-condition

• Established Service Level Connection• Internal event or user requested: Enable CLI notification

Application layer

Feature HF AG

13. Calling Line Identification(CLI) O O

• The HF Requests Turning Off the AG’s EC and NR – Pre-condition : Established Service Level Connection

• If the HF has embedded EC and/or NR functions enabled, it shall perform this procedure before any Audio Connection between the HF and the AG is established.

Application layer

Feature HF AG

14. Echo canceling(EC) and noise reduction(NR)

O O

Application layer

Feature HF AG

15. Voice recognition activation O O

• Voice Recognition Activation– Pre-condition

• Established Service Level Connection(or optionally an Audio Connection)

– Voice Recognition Activation – HF Initiated – Voice Recognition Activation – AG Initiated

• Voice Recognition Deactivation – Pre-condition

• Established Service Level Connection• Voice recognition is enabled

– Voice recognition deactivation from the HF– Voice recognition deactivation from the AG

Application layer

Feature HF AG

16. Attach a Phone number to a voice tag O O

• Attach a Phone Number to a Voice Tag – read numbers from the AG for the purpose of creating a

unique voice tag and storing the number and its linked voice tag in the HF unit’s memory.

User Insert Phone

numberStore The Voice Tag and Phone

Number

Application layer

Feature HF AG

17. Ability to transmit DTMF codes O M

• Transmit DTMF Codes – Pre-condition :

• Established Service Level Connection• An ongoing call in the AG exists

Application layer

Feature HF AG

18. Remote audio volume control O O

• Audio Volume Control – Enables the user to modify the speaker volume and

microphone gain of the HF from the AG• On a scale from 0 to 15• The values are absolute values• Relate to a particular volume level controlled by the HF

• Volume Level Synchronization – This procedure allows the HF to inform the AG of the

current gain settings corresponding to the HF’s speaker volume and microphone gain.

AG HF

HF AG

Application layer

Feature HF AG

19. Respond and Hold O O

• Query Response and Hold Status• Put an Incoming Call on Hold from HF • Put an Incoming Call on Hold from AG • Accept a Held Incoming Call from HF • Accept a Held Incoming Call from AG • Reject a Held Incoming Call from HF • Reject a Held Incoming Call from AG • Held Incoming Call Terminated by Caller

Application layer

Feature HF AG

19. Respond and Hold O O

AT+BTRH? (Read Current Status) AT+BTRH=<n> (Set command) 0 = Put Incoming call on hold 1 = Accept a held incoming call 2 = Reject a held incoming call

+BTRH: <n> (Response for AT+BTRH) 0 = Incoming call is put on hold in the AG 1 = Held incoming call is accepted in the AG 2 = Held incoming call is rejected in the AG

Application layer

Feature HF AG

20. Subscriber Number Information O M

• HF to query the AG subscriber number– Pre-condition: Established Service Level Connection– AG response to the query of Empty, One or multiple

subscriber number

Application layer

Feature HF AG

21a. Enhanced Call Status O M

• Query List of Current Calls in AG – Pre-condition: Established Service Level Connection

• Indication of Status for Held Calls – Pre-condition

• Established Service Level Connection• The HF shall have enabled the Call Status Indicators

function in the AG

– Values for the callheld indicator• 0= No calls held• 1= Call is placed on hold or active/held calls swapped

(The AG has both and active AND a held call) • 2= Call on hold, no active call (terminate active call only)

Application layer

Feature HF AG

21b. Enhanced Call Controls O O

• Release Specified Call Index – Pre-condition

• Established Service Level Connection• Existing call

• Private Consultation Mode – Pre-condition

• Established Service Level Connection• Existing multiparty call

– Place all calls on hold EXCEPT the call indicated.