388. Bluetooth profile

Bluetooth profile

A Bluetooth profile is a specification regarding an aspect of Bluetooth-based wireless communication between devices. In order to use Bluetooth technology, a device must be compatible with the subset of Bluetooth profiles necessary to use the desired services.
A Bluetooth profile resides on top of the Bluetooth Core Specification and (optionally) additional protocols.
While the profile may use certain features of the core specification, specific versions of profiles are rarely tied to specific versions of the core specification. For example, there are Hands-Free Profile (HFP) 1.5 implementations using both Bluetooth 2.0 and Bluetooth 1.2 core specifications.
The way a device uses Bluetooth technology depends on its profile capabilities. The profiles provide standards which manufacturers follow to allow devices to use Bluetooth in the intended manner. For the Bluetooth low energy stack according to Bluetooth V4.0 a special set of profiles applies.
At a maximum, each profile specification contains information on the following topics:

• Dependencies on other formats
• Suggested user interface formats
• Specific parts of the Bluetooth protocol stack used by the profile. To perform its task, each profile uses particular options and parameters at each layer of the stack. This may include an outline of the required service record, if appropriate.

This article summarizes the current definitions and possible applications of each profile.

List of profiles

The following profiles are defined and adopted by the Bluetooth SIG:

Advanced Audio Distribution Profile (A2DP)

This profile defines how high quality audio(stereo or mono) can be streamed from one device to another over a Bluetooth connection. For example, music can be streamed from a mobile phone, to a wireless headset, hearing aid & cochlear implant streamer, car audio, or from a laptop/desktop to a wireless headset.
A2DP was initially used in conjunction with an intermediate Bluetooth transceiver that connects to a standard audio output jack, encodes the incoming audio to a Bluetooth-friendly format, and sends the signal wirelessly to Bluetooth headphones that decode and play the audio. Bluetooth headphones, especially the more advanced models, often come with a microphone and support for the Headset (HSP), Hands-Free (HFP) and Audio/Video Remote Control (AVRCP) profiles.
A2DP is designed to transfer a uni-directional 2-channel stereo audio stream, like music from an MP3 player, to a headset or car radio. This profile relies on AVDTP and GAVDP. It includes mandatory support for the low-complexity SBC codec (not to be confused with Bluetooth's voice-signal codecs such as CVSDM), and supports optionally: MPEG-1, MPEG-2, MPEG-4, AAC, and ATRAC, and is extensible to support manufacturer-defined codecs, such as apt-X. Some Bluetooth stacks enforce the SCMS-T digital rights management (DRM) scheme. In these cases, it is impossible to connect certain A2DP headphones for high quality audio.

Attribute Profile (ATT)

The ATT is a wire application protocol for Bluetooth Low Energy specification. It is closely related to Generic Attribute Profile (GATT).

Audio/Video Remote Control Profile (AVRCP)

This profile is designed to provide a standard interface to control TVs, Hi-fi equipment, etc. to allow a single remote control (or other device) to control all of the A/V equipment to which a user has access. It may be used in concert with A2DP or VDP.
It has the possibility for vendor-dependent extensions.
AVRCP has several versions with significantly increasing functionality:

• 1.0—Basic remote control commands (play/pause/stop, etc.)
• 1.3—all of 1.0 plus metadata and media-player state support
• The status of the music source (playing, stopped, etc.)
• Metadata information on the track itself (artist, track name, etc.).
• 1.4—all of 1.0, 1.3, plus media browsing capabilities for multiple media players
• Browsing and manipulation of multiple players
• Browsing of media metadata per media player, including a "Now Playing" list
• Basic search capabilities

Basic Imaging Profile (BIP)

This profile is designed for sending images between devices and includes the ability to resize, and convert images to make them suitable for the receiving device. It may be broken down into smaller pieces:

Image Push 

Allows the sending of images from a device the user controls.

Image Pull 

Allows the browsing and retrieval of images from a remote device.

Advanced Image Printing 

print images with advanced options using the DPOF format developed by Canon, Kodak, Fujifilm, and Matsushita

Automatic Archive 

Allows the automatic backup of all the new images from a target device. For example, a laptop could download all of the new pictures from a camera whenever it is within range.

Remote Camera 

Allows the initiator to remotely use a digital camera. For example, a user could place a camera on a tripod for a group photo, use their phone handset to check that everyone is in frame, and activate the shutter with the user in the photo.

Remote Display 

Allows the initiator to push images to be displayed on another device. For example, a user could give a presentation by sending the slides to a video projector.

Basic Printing Profile (BPP)

This allows devices to send text, e-mails, vCards, or other items to printers based on print jobs. It differs from HCRP in that it needs no printer-specific drivers. This makes it more suitable for embedded devices such as mobile phones and digital cameras which cannot easily be updated with drivers dependent upon printer vendors.

Common ISDN Access Profile (CIP)

This provides unrestricted access to the services, data and signalling that ISDN offers.

Cordless Telephony Profile (CTP)

This is designed for cordless phones to work using Bluetooth. It is hoped that mobile phones could use a Bluetooth CTP gateway connected to a landline when within the home, and the mobile phone network when out of range. It is central to the Bluetooth SIG's '3-in-1 phone' use case.

Device ID Profile (DIP)

This profile allows a device to be identified above and beyond the limitations of the Device Class already available in Bluetooth. It enables identification of the manufacturer, product id, product version, and the version of the Device ID specification being met. It is useful in allowing a PC to identify a connecting device and download appropriate drivers. It enables similar applications to those the Plug-and-play specification allows.

Dial-up Networking Profile (DUN)

This profile provides a standard to access the Internet and other dial-up services over Bluetooth. The most common scenario is accessing the Internet from a laptop by dialing up on a mobile phone, wirelessly. It is based on Serial Port Profile (SPP), and provides for relatively easy conversion of existing products, through the many features that it has in common with the existing wired serial protocols for the same task. These include the AT command set specified in European Telecommunications Standards Institute (ETSI) 07.07, and Point-to-Point Protocol (PPP).
DUN distinguishes the initiator (DUN Terminal) of the connection and the provider (DUN Gateway) of the connection. The gateway provides a modem interface and establishes the connection to a PPP gateway. The terminal implements the usage of the modem and PPP protocol to establish the network connection. In standard phones, the gateway PPP functionality is usually implemented by the access point of the Telco provider. In "always on" smartphones, the PPP gateway is often provided by the phone and the terminal shares the connection.

Fax Profile (FAX)

This profile is intended to provide a well-defined interface between a mobile phone or fixed-line phone and a PC with Fax software installed. Support must be provided for ITU T.31 and / or ITU T.32 AT command sets as defined by ITU-T. Data and voice calls are not covered by this profile.

File Transfer Profile (FTP)

Provides the capability to browse, manipulate and transfer objects (files and folders) in an object store (file system) of another system. Uses GOEP as a basis.

Generic Audio/Video Distribution Profile (GAVDP)

Provides the basis for A2DP, and VDP.

Generic Access Profile (GAP)

Provides the basis for all other profiles. GAP defines how two Bluetooth units discover and establish a connection with each other.

Generic Attribute Profile (GATT)

Provides profile discovery and description services for Bluetooth Low Energy protocol. It defines how a set of ATT attributes are grouped together to form services.

Generic Object Exchange Profile (GOEP)

Provides a basis for other data profiles. Based on OBEX and sometimes referred to as such.

Hard Copy Cable Replacement Profile (HCRP)

This provides a simple wireless alternative to a cable connection between a device and a printer. Unfortunately it does not set a standard regarding the actual communications to the printer, so drivers are required specific to the printer model or range. This makes this profile less useful for embedded devices such as digital cameras and palmtops, as updating drivers can be problematic.

Health Device Profile (HDP)

Profile designed to facilitate transmission and reception of Medical Device data. The API's of this layer interact with the lower level Multi-Channel Adaptation Protocol (MCAP layer), but also perform SDP behavior to connect to remote HDP devices. Also makes use of the Device ID Profile (DIP).

Hands-Free Profile (HFP)

Currently in version 1.6, this is commonly used to allow car hands-free kits to communicate with mobile phones in the car. It commonly uses Synchronous Connection Oriented link (SCO) to carry a monaural audio channel with continuously variable slope delta modulation or pulse-code modulation, and with logarithmic a-law or μ-law quantization. Version 1.6 adds optional support for wide band speech with the mSBC codec, a 16 kHz monaural configuration of the SBC codec mandated by the A2DP profile.
In 2002 Audi, with the Audi A8, was the first motor vehicle manufacturer to install Bluetooth technology in a car, enabling the passenger to use a wireless in-car phone. The following year DaimlerChrysler and Acura introduced Bluetooth technology integration with the audio system as a standard feature in the third-generation Acura TL in a system dubbed HandsFree Link (HFL). Later, BMW added it as an option on its 1 Series, 3 Series, 5 Series, 7 Series and X5 vehicles. Since then, other manufacturers have followed suit, with many vehicles, including the Toyota Prius (since 2004), 2007 Toyota Camry, 2007 Infiniti G35, and the Lexus LS 430 (since 2004). Several Nissan models (Versa, X-Trail) include a built-in Bluetooth for the Technology option. Volvo started introducing support in some vehicles in 2007, and as of 2009 all Bluetooth-enabled vehicles support HFP.^[2]
Many manufacturers like Pioneer or JVC builds car radios with bluetooth module. This module usually has HSP support.
The Bluetooth car kits allow users with Bluetooth-equipped cell phones to make use of some of the phone's features, such as making calls, while the phone itself can be left in the user's pocket or hand bag. Companies like Johnson Controls, Peiker acustic, RAYTEL, Parrot SA, Novero, S1NN and Motorola manufacture Bluetooth hands-free car kits for well-known brand car manufacturers.
Most bluetooth headsets implement both Hands-Free Profile and Headset Profile, because of the extra features in HFP for use with a mobile phone, such as last number redial, call waiting and voice dialing.

Human Interface Device Profile (HID)

Provides support for devices such as mice, joysticks, keyboards, as well as sometimes providing support for simple buttons and indicators on other types of devices. It is designed to provide a low latency link, with low power requirements. PlayStation 3 controllers and Wii Remotes also use Bluetooth HID.
Bluetooth HID is a lightweight wrapper of the Human Interface Device protocol defined for USB. The use of the HID protocol simplifies host implementation (ex: support by Operating Systems) by enabling the re-use of some of the existing support for USB HID to also support Bluetooth HID.

Headset Profile (HSP)

This is the most commonly used profile, providing support for the popular Bluetooth Headsets to be used with mobile phones. It relies on SCO for audio encoded in 64 kbit/s CVSD or PCM and a subset of AT commands from GSM 07.07 for minimal controls including the ability to ring, answer a call, hang up and adjust the volume.

Intercom Profile (ICP)

This is often referred to as the walkie-talkie profile. It is another TCS (Telephone Control protocol Specification)^[3] based profile, relying on SCO to carry the audio. It is proposed to allow voice calls between two Bluetooth capable handsets, over Bluetooth.

LAN Access Profile (LAP)

LAN Access profile makes it possible for a Bluetooth device to access LAN, WAN or Internet via another device that has a physical connection to the network. It uses PPP over RFCOMM to establish connections. LAP also allows the device to join an ad-hoc Bluetooth network.
The LAN Access Profile has been replaced by the PAN profile in the Bluetooth specification.

Message Access Profile (MAP)

Message Access Profile (MAP)^[4] specification allows exchange of messages between devices. Mostly used for automotive handsfree use. The MAP profile can also be used for other uses that require the exchange of messages between two devices. The automotive Hands-Free use case is where an on-board terminal device (typically an electronic device as a Car-Kit installed in the car) can talk via messaging capability to another communication device (typically a mobile phone). For example, Bluetooth MAP is used by HP Send and receive text (SMS) messages from a Palm/HP smartphone to an HP TouchPad tablet.^[5] Bluetooth MAP is used by Ford in select SYNC Generation 1-equipped 2011 and 2012 vehicles ^[6] and also by BMW with many of their iDrive systems. The Lexus LX and GS 2013 models both also support MAP as does the Honda CRV 2012, Acura 2013 and ILX 2013. Apple introduced Bluetooth MAP in iOS 6 for the iPhone and iPad.

OBject EXchange (OBEX)

See OBEX.

Object Push Profile (OPP)

A basic profile for sending "objects" such as pictures, virtual business cards, or appointment details. It is called push because the transfers are always instigated by the sender (client), not the receiver (server).
OPP uses the APIs of OBEX profile and the OBEX operations which are used in OPP are connect, disconnect, put, get and abort. By using these API the OPP layer will reside over OBEX and hence follow the specifications of the Bluetooth stack.

Personal Area Networking Profile (PAN)

This profile is intended to allow the use of Bluetooth Network Encapsulation Protocol on Layer 3 protocols for transport over a Bluetooth link.

Phone Book Access Profile (PBAP, PBA)

Phone Book Access (PBA) or Phone Book Access Profile (PBAP) is a profile that allows exchange of Phone Book Objects between devices. It is likely to be used between a car kit and a mobile phone to:

• allow the car kit to display the name of the incoming caller;
• allow the car kit to download the phone book so the user can initiate a call from the car display.

The profile consists of two roles:

• PSE - Phone Book Server Equipment for the side delivering phonebook data, like a mobile phone
• PCE - Phone Book Client Equipment, for the device receiving this data, like a personal navigation device (PND)

Serial Port Profile (SPP)

This profile is based on ETSI 07,10 and the RFCOMM protocol. It emulates a serial cable to provide a simple substitute for existing RS-232, including the familiar control signals. It is the basis for DUN, FAX, HSP and AVRCP.

Service Discovery Application Profile (SDAP)

SDAP describes how an application should use SDP to discover services on a remote device. SDAP requires that any application be able to find out what services are available on any Bluetooth enabled device it connects to.

SIM Access Profile (SAP, SIM, rSAP)

This allows devices such as car phones with built-in GSM transceivers to connect to a SIM card in a phone with Bluetooth, thus the car phone itself doesn't require a separate SIM card. This profile is also known as rSAP (remote-SIM-Access-Profile). More information on which phones are supported can be found here(German version only)

Synchronization Profile (SYNCH)

This profile allows synchronization of Personal Information Manager (PIM) items. As this profile originated as part of the infrared specifications but has been adopted by the Bluetooth SIG to form part of the main Bluetooth specification, it is also commonly referred to as IrMC Synchronization.

Video Distribution Profile (VDP)

This profile allows the transport of a video stream. It could be used for streaming a recorded video from a PC media center to a portable player, or a live video from a digital video camera to a TV. Support for the H.263 baseline is mandatory. The MPEG-4 Visual Simple Profile, and H.263 profiles 3 and 8 are optionally supported, and covered in the specification.1

Wireless Application Protocol Bearer (WAPB)

This is a profile for carrying Wireless Application Protocol (WAP) over Point-to-Point Protocol over Bluetooth.

Comments

These profiles are still not finalised, but are currently proposed within the Bluetooth SIG:

• Unrestricted Digital Information (UDI)
• Extended Service discovery profile (ESDP)
• Video Conferencing Profile (VCP) : This profile is to be compatible with 3G-324M, and support videoconferencing over a 3G high-speed connection.

Compatibility of products with profiles can be verified on the Bluetooth Qualification Program website.

387. Astroparticle physics

Astroparticle physics

Astroparticle physics, the same as particle astrophysics, is a branch of particle physics that studies elementary particles of astronomical origin and their relation to astrophysics and cosmology.
It is a relatively new field of research emerging at the intersection of particle physics, astronomy, astrophysics, detector physics, relativity, solid state physics, and cosmology. Partly motivated by the historic discovery of neutrino oscillations, the field has undergone remarkable development, both theoretically and experimentally, over the last decade.

History

The field of astroparticle physics is evolved out of optical astronomy. With the growth of detector technology came the more mature astrophysics, which involved multiple physics subtopics, like

1.      Mechanics,

2.      electrodynamics,

3.      thermodynamics,

4.      plasma physics,

5.      nuclear physics,

6.      Relativity, and

7.      particle physics.

Particle physicist found astrophysics necessary due to difficulty in performing comparable experiments to those found in nature. For example the energy scale in the cosmic ray spectrum can see energies as high as 10^20 eV, where a proton-antiproton collision at the Large Hadron Collider produces energies on the scale of TeV.
The field can be said to have begun in 1910, when a German physicist named Theodor Wulf measured the ionization in the air, an indicator of gamma radiation, at the bottom and top of the Eiffel Tower. He found that there was far more ionization at the top than what was expected if only terrestrial sources were attributed for this radiation.^[1]
Victor Francis Hess, then an Austrian physicist, hypothesized that some of the ionization was caused by radiation from the sky. In order to defend this hypothesis, Hess designed instruments capable of operating at high altitudes and performed observations on ionization up to an altitude of 5.3 km. From 1911 to 1913, Hess made ten flights to meticulously measure ionization levels. Through prior calculations, he did not expect there to be any ionization at an altitude of 500m if terrestrial sources were the sole cause of radiation. His measurements however, revealed that although the ionization levels initially decreased with altitude, they began to sharply rise at some point. At the peaks of his flights, he found that the ionization levels were much greater than at the surface. Hess was then able to conclude that “a radiation of very high penetrating power enters our atmosphere from above.” Furthermore, one of Hess’s flights was during a near-total eclipse of the Sun. Since he did not observe a dip in ionization levels, Hess reasoned that the source had to be further away in space. For this discovery, Hess was one of the people awarded the Nobel Prize in Physics in 1936. In 1925, Robert Millikan confirmed Hess’s findings and subsequently coined the term ‘cosmic rays’.
Many physicists knowledgeable about the origins of the field of astroparticle physics prefer to attribute this ‘discovery’ of cosmic rays by Hess as the starting point for the field.^[3]

Topics of Research

While it may be difficult to decide on a standard 'textbook' description of the field of astroparticle physics, the field can be characterized by the topics of research that are actively being pursued. The Astroparticle Physics journal, published by Elsevier, accepts papers that are focused on new developments in the following areas:

• High-energy cosmic-ray physics and astrophysics;
• Particle cosmology;
• Particle astrophysics;
• Related astrophysics: Supernova, Active Galactic Nuclei, Cosmic Abundances, Dark Matter etc.;
• High-energy, VHE and UHE gamma-ray astronomy;
• High- and low-energy neutrino astronomy;
• Instrumentation and detector developments related to the above-mentioned fields.

Open Questions

One main task for the future of the field is simply to thoroughly define itself beyond working definitions and clearly differentiate itself from astrophysics and other related topics.
A current unsolved problem for the field of astroparticle physics is dark matter and dark energy. Observations of the orbital velocities of stars in the Milky Way and the velocities of galaxies in galactic clusters, the energy density of the visible matter in the universe is far too insufficient to account for the dynamics. Since the early nineties some candidates have been found to partially explain some of the missing dark matter, but they are nowhere near sufficient to offer a full explanation. The finding of an accelerating universe suggests that a large part of the missing dark matter is stored as dark energy in a dynamical vacuum.
Another question for astroparticle physicists is why is there so much more matter than antimatter in the universe today. Baryogenesis is the term for the hypothetical processes that produced the unequal numbers of baryons and anitbaryons in the early universe, which is why the universe is made of matter today, and not antimatter.

Experimental Facilities

The rapid development of this field has led to the design of new types of infrastructure. In underground laboratories or with specially designed telescopes, antennas and satellite experiments, astroparticle physicists employ new detection methods to observe a wide range of cosmic particles including neutrinos, gamma rays and cosmic rays at the highest energies. They are also searching for dark matter and gravitational waves. Experimental particle physicists are limited by the technology of their terrestrial accelerators, which are only able to produce a small fraction of the energies found in nature.

Facilities, experiments and laboratories involved in astroparticle physics include:

• IceCube (Antarctica). The longest particle detector in the world, was completed in December 2010. The purpose of the detector is to investigate high energy neutrinos, search for dark matter, observe supernovae explosions, and search for exotic particles such as magnetic monopoles.^[7]
• ANTARES (telescope). (Toulon, France). A Neutrino detector 2.5 km under the Mediterranean Sea off the coast of Toulon, France. Designed to locate and observe neutrino flux in the direction of the southern hemisphere.
• Pierre Auger Observatory (Pampa Amarilla, Argentina). Detects and investigates high energy cosmic rays using two techniques. One is to study the particles interactions with water placed in surface detector tanks. The other technique is to track the development of air showers through observation of ultraviolet light emitted high in the Earth's atmosphere.^[8]
• CERN Axion Solar Telescope (CERN, Switzerland). Searches for axions originating from the Sun.
• NESTOR Project (Pylos, Greece). The target of the international collaboration is the deployment of a neutrino telescope on the sea floor off of Pylos, Greece.
• Laboratori Nazionali del Gran Sasso (L'Aquila, Italy). Located within the Gran Sasso mountain with its experimental halls covered by 1400m of rock, which protects experiments from cosmic rays. The facility hosts experiments that require a low noise background environment.
• Aspera European Astroparticle network Started in July 2006 and is responsible for coordinating and funding national research efforts in Astroparticle Physics.
• SNOLAB

386. 60 nanoseconds quicker than light

60 nanoseconds quicker than light

(Reuters) - An international team of scientists said on Thursday they had recorded sub-atomic particles traveling faster than light -- a finding that could overturn one of Einstein's long-accepted fundamental laws of the universe.
Antonio Ereditato, spokesman for the researchers, told Reuters that measurements taken over three years showed neutrinos pumped from CERN near Geneva to Gran Sasso in Italy had arrived 60 nanoseconds quicker than light would have done.
"We have high confidence in our results. We have checked and rechecked for anything that could have distorted our measurements but we found nothing," he said. "We now want colleagues to check them independently."
If confirmed, the discovery would undermine Albert Einstein's 1905 theory of special relativity, which says that the speed of light is a "cosmic constant" and that nothing in the universe can travel faster.

That assertion, which has withstood over a century of testing, is one of the key elements of the so-called Standard Model of physics, which attempts to describe the way the universe and everything in it works.
The totally unexpected finding emerged from research by a physicists working on an experiment dubbed OPERA run jointly by the CERN particle research center near Geneva and the Gran Sasso Laboratory in central Italy.
A total of 15,000 beams of neutrinos -- tiny particles that pervade the cosmos -- were fired over a period of 3 years from CERN toward Gran Sasso 730 (500 miles) km away, where they were picked up by giant detectors.
Light would have covered the distance in around 2.4 thousandths of a second, but the neutrinos took 60 nanoseconds -- or 60 billionths of a second -- less than light beams would have taken.
"It is a tiny difference," said Ereditato, who also works at Berne University in Switzerland, "but conceptually it is incredibly important. The finding is so startling that, for the moment, everybody should be very prudent."
Ereditato declined to speculate on what it might mean if other physicists, who will be officially informed of the discovery at a meeting in CERN on Friday, found that OPERA's measurements were correct.
"I just don't want to think of the implications," he told Reuters. "We are scientists and work with what we know."
Much science-fiction literature is based on the idea that, if the light-speed barrier can be overcome, time travel might theoretically become possible.
The existence of the neutrino, an elementary sub-atomic particle with a tiny amount of mass created in radioactive decay or in nuclear reactions such as those in the Sun, was first confirmed in 1934, but it still mystifies researchers.
It can pass through most matter undetected, even over long distances, and without being affected. Millions pass through the human body every day, scientists say.
To reach Gran Sasso, the neutrinos pushed out from a special installation at CERN -- also home to the Large Hadron Collider probing the origins of the universe -- have to pass through water, air and rock.
The underground Italian laboratory, some 120 km (75 miles) to the south of Rome, is the largest of its type in the world for particle physics and cosmic research.
Around 750 scientists from 22 different countries work there, attracted by the possibility of staging experiments in its three massive halls, protected from cosmic rays by some 1,400 metres (4,200 feet) of rock overhead.