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Bluetooth 4 data transfer speed. How to choose a Bluetooth device for listening to music

Recently, the number of users of mobile gadgets has increased significantly, which means that a large number of different technical issues remain dark horses for novice users. One of these nuances is Bluetooth versions.

Protocols or profiles

Despite the fact that the compatibility of Bluetooth versions is at a fairly high level, situations still sometimes occur in which it becomes impossible to pair two devices. And the point here is precisely in the protocols, and not in the profiles. And in order to justify the above-mentioned impossibility, you first need to understand what the difference is between these two concepts.

A protocol is a set of instructions through which various information is transmitted. It is he who sets the order, operating frequency and duration of operation of one or another component. And profiles are additional add-ons that allow you to operate with information of a certain type. For example, A2DP is a profile that allows a Bluetooth module to work with stereo sound, where during pairing the codecs that will be used are also agreed upon.

If you look at it from a global perspective, the version of the protocols matters more than the significance of the profile. If both devices have the same protocol version, then they will have access to all the standard functions and capabilities that the module supports. But with profiles everything is different. Since they are added optionally, in order for them to be used and work, they will need to be present in both gadgets. If only one Bluetooth module supports the required profile, it will not be used during data transfer.

Many users are interested in the question of how to find out the bluetooth version. There are several ways to do this, but the easiest way is to read the device specification. But it is much more important to understand what is hidden behind these numbers.

How to find out the Bluetooth version: Video

Technical data of various protocols

This description will not contain the most complete list of protocol versions, but only the most significant for the entire technology as a whole. And, of course, it’s worth starting with the very first one, which was created almost two decades ago almost two decades ago - in 1998, by the partner group SIG or Special Interested Group. The primary development was established by the then Swedish company Ericsson 4 years before entering the market. As a result of successful research, a worthy analogue of wired technology was created and named after the Danish king of the Viking northerners, Harald the First Bluetooth.

The first version had amazing compatibility between devices from different manufacturers. The speed was tiny, and the range was clearly not up to the established standard. If it were not for prompt attempts to refine the technology, the whole idea could have sunk into oblivion. And the professional qualities of the workers did not disappoint, because soon version 1.1 was released, and then 1.2, which became the pinnacle of the evolution of the first generation modules. The general compatibility was raised to a fairly high level, the range of action was set to an honest ten meters, the transmission speed was made simply sky-high - 721 Kbps, theoretically, of course.

Version 2.1

The second generation made a revolution, but it was version 2.1 that became the guiding light that is still used today. Many entry-level and middle-class devices use this particular variation of the Bluetooth module. The main focus was on speed, and the solution was the EDR add-on. It was thanks to it that it became possible to transmit at speeds close to 3 Mbit/s, and the level of energy consumption was reduced five times. Of course, various profiles and add-ons have appeared, including the ability to distribute network access.

Third version

The high-speed specification 3.0 had much in common with Wi-Fi, but was not directly compatible with it, and the use of SLI technology, by which two Bluetooth modules were connected into one system, made it possible to increase the transfer speed to 24 Mbit/s. Moreover, when moving large files, a higher-speed, but also energy-consuming protocol was used, and for small files it was very economical.

The fourth generation of devices was based on the idea of ​​improving the previous technology so that power consumption became minimal, and all other functions and capabilities were increased and expanded. So, in addition to speed, the radius was also increased, which could now reach hundreds of meters. Data packets have become more optimal in size, and 128-bit encryption has been added. The dimensions of the transmitter have become simply tiny, which makes it possible to use them everywhere. One of the highlights was the addition of three operating modes.

Come in and remember how it all began.

How do you personally feel about wires? Let's outline a very unusual and even somewhat funny situation.

Apple Watch connects to a smartphone via the Lightning port (it doesn’t work without it); the athlete has no choice in what to listen to music - only wires, only hardcore; all “smart” equipment in the house only works when the smartphone is connected “via a cord”...

Not a very bright prospect, right?

Gadgetman's nightmare

And all this could be today's reality if 20 years ago large corporations had not thought about creating a unified wireless data transmission technology with a short range - Bluetooth.

It's time to unite

A number of manufacturers such as Ericsson, Nokia, Intel, Toshiba and dozens of others are thinking about creating a unified standard for wireless data transfer. Having joined forces and gathered all the engineering potential into a single group, on May 20, 1998, the above companies officially joined the so-called SIG - Special Interest Group.

The purpose of this "common interest group" was to introduce wireless data technology Bluetooth. And most importantly, the new technology had to become unified, putting an end to confusion and compatibility of devices when wireless pairing is necessary.

Dell, Xircom, Motorola, Compaq, Qualcomm - all these brands will soon be part of SIG.

And today the SIG membership includes more than 30,000 companies from all over the world. Bluetooth has long been taken for granted and the number of devices in which this wireless communication protocol is integrated is beyond counting.

Meanwhile, the estimated number of devices that support Bluetooth connectivity is about 8.2 billion devices.

First went: Bluetooth 1.0–1.2


In 1998, many businessmen dreamed about it

The first wireless protocol was Bluetooth 1.0, announced in 1998. The first version obviously could not do without shortcomings and errors.

Among the key problems are a very unstable signal and constant connection interruptions. Moreover, manufacturers began to note the lack of proper compatibility of devices. For example, two different companies that released two compatible devices on the market could not be sure that the user would be able to connect them via Bluetooth.

They immediately rushed to save the situation and a year later introduced the updated Bluetooth 1.0B. It got better, but it was still far from ideal. Bluetooth 1.0(B) required the mandatory transmission of the device address, which means there was no point in talking about any anonymity. This became the main drawback of the protocol at its inception stage. In 2000, the presentation of the updated Bluetooth 1.1 took place. Now users could determine the signal strength of a wireless connection and transmit data over unencrypted channels.


Legendary Bluetooth 1.2 compatible headset from Motorola

The first global update was Bluetooth 1.2, which received a number of improvements at once: from increasing the data transfer rate (up to 1 Mbit/s) and improving noise immunity to supporting the A2DP profile, which for the first time made it possible to transmit stereo sound.

Time to grow up: Bluetooth 2.0 – 2.1 (EDR)


An amateur developer's dream - Bluetooth 2.0 module for Arduino

In 2004, manufacturers waited for Bluetooth 2.0. Among the innovations in this version:

  • Increased data transfer speed. According to the documentation, Bluetooth 2.0 had a throughput of 3 Mbps, but practice is a merciless thing. The maximum that could be squeezed out of Bluetooth 2.0 was 2.1 Mb/s.
  • The emergence of EDR technology, which indicated a more advanced version of the protocol, directly affecting the speed.
  • Additional bandwidth for synchronous connection of multiple devices.
  • Slight reduction in energy consumption.

The next update dates back to 2007. For three years, engineers have been working on the possibility of reducing the protocol's gluttony in relation to the battery of portable devices and, together with Bluetooth 2.1, announced a new technology called Sniff Subrating. The energy efficiency of the new “bluetooth” has increased up to 10 times, and pairing devices has become much easier.

In the same year, NFC (Near Field Communication) technology was released, which is responsible for properly protecting the connection.

Almost Wi-Fi: Bluetooth 3.0 + HS


These are the Link Dream smartwatches in 2009

On April 21, 2009, the new Bluetooth 3.0 standard was adopted. This time, the engineers set themselves the goal of significantly increasing data transfer speeds. In theory, the result was 24 Mbit/s.

Bluetooth 3.0 included two versions of the radio system: standard 2.0 (up to 3 MB/s) and 802.11 compatible high-speed (up to 24 MB/s).

Depending on the size of the transferred file, the version of the radio system also changes. Despite using the 802.11 standard, Bluetooth 3.0 is not compatible with any Wi-Fi specification.

Dieter: Bluetooth 4.0 – 4.2


iPhone 4s became the first smartphone to support Bluetooth 4.0

The third version of Bluetooth lasted only a year. A number of manufacturers did not have time to thoroughly “get hooked” on the new standard, when on June 30, 2010, SIG approved Bluetooth 4.0 - a new word in the life of wireless technology.

The main emphasis of the technology is extremely low power consumption. The developers relied on the integration of Bluetooth 4.0 into miniature gadgets, sensors, sensors and other devices that cannot accommodate a capacious battery.

As a result, Bluetooth 4.0 worked on a completely different principle. Instead of being constantly active, it turns on only at the moment of sending or receiving data, significantly saving the device’s battery power.

For example, a miniature sensor can operate for several years on a CR2032 battery:

The range has been increased to 100 meters, the data transfer rate, for the sake of energy efficiency, has been reduced to 1 Mbit/s.

Over the next four years, Bluetooth 4.0 received two more updates: 4.1, with an emphasis on compatibility with LTE networks, and 4.2, with increased throughput speed (2.5 times) and improved security.

Bluetooth 5.0

The history of the protocol's development continues to be created right before our eyes. On June 17, 2016, SIG announced a new specification.

It will take a little time to appreciate the updated technology. The first devices with Bluetooth 5.0 will not appear until the end of this year or the beginning of next year, but today the developers have promised:

  • 4 times increased data transfer speed compared to version 4.2
  • double the signal range
  • reduced power consumption compared to Wi-Fi modules

But the most interesting thing is that Bluetooth 5.0 has received the prefix “Smart”, which means the “intelligence” of mobile gadgets will become even more advanced. A bright future is just beginning!

Wireless Bluetooth headsets- this is the category of precisely those devices that have remained the engine of technology development for 18 years. Headsets have evolved from low-quality crackling sound with minimal battery life to stylish fashion accessories that are simply a pleasure to talk through.

Our choice in the Bluetooth headsets segment:

  • Excellent and crystal sound with Plantronics Explorer 500
  • Unique design and excellent voice quality

Before Bluetooth 3.0 gained popularity, it was replaced by Bluetooth 4.0. The Bluetooth SIG approved the Bluetooth 4.0 specification on June 30, 2010. Bluetooth 4.0 includes the following protocols - Classic Bluetooth, Bluetooth High Speed, and Bluetooth Low Energy. High Speed ​​Bluetooth is based on Wi-Fi, while Classic Bluetooth consists of protocols from previous Bluetooth specifications.

The Bluetooth Low Energy protocol was designed primarily for miniature electronic sensors (used in sports shoes, exercise equipment, miniature sensors placed on the body of patients, etc. - example below in the video). Low power consumption is achieved through the use of a special operating algorithm. The transmitter is turned on only while sending data, which makes it possible to operate on a single CR2032 battery for several years. The standard provides a data transfer rate of 1 Mbit/s with a data packet size of 8-27 bytes. In the new version, two Bluetooth devices will be able to establish a connection in less than 5 milliseconds and maintain it at a distance of up to 100 m. Advanced error correction is used for this, and the necessary level of security is provided by 128-bit AES encryption.

Sensors for temperature, pressure, humidity, speed of movement, etc. based on this standard can transmit information to various control devices: mobile phones, PDAs, PCs, etc.
It is worth recalling that Nokia created a similar technology called Wibree back in 2004, borrowing the basic principles of Bluetooth. The company created its design from cheaper components with a short communication range and ultra-low power consumption.

When purchasing a wireless Bluetooth speaker Sony XB-40, it became necessary to purchase a Bluetooth adapter, since the computer does not have a built-in Bluetooth module, and with a wired connection to the speaker it will not connect via Bluetooth from the phone.
I read on the Internet that the ORICO bta-403 adapter is the best choice for little money.



The Bluetooth module is supplied in a plastic blister.

Available in 4 body colors:

Dimensions:




Equipment:
- Bluetooth module
- Liner
Operating system compatibility
* Windows XP, 2003, Vista, 7.2008 and Windows 8 32 or 64 bit

The build quality of the adapter is good; the body is plastic and consists of two halves.


Explosion diagram of the module:

ORICO BTA-403 runs on the Qualcomm CSR8510 chipset with support for the Bluetooth 4.0 + EDR 3.0 protocol. The module supports A2DP, PAN, ATT, AVRCP, PAN, GAVDP, HCRP, HFP, HID, HID over GATT, GATT, OPP profiles.

Bluetooth is a protocol stack that allows communication between various devices over a distance without the use of wires:
- up to 100 m for Class 1 (industrial systems);
- up to 10 m for Class 2 (household equipment);
- up to 1 m for Class 3 (medical equipment).
Bluetooth can be used to transmit various types of data.

Bluetooth adapter profiles

A2DP (Advanced Audio Distribution Profile) - provides transmission of a two-channel (stereophonic) audio stream from a signal source (PC, player, mobile phone) to a wireless stereo headset, speaker system or other playback device.

AVRCP (Audio/Video Remote Control Profile) - allows you to control standard functions of TVs, home theater systems, etc. A device that supports the AVRCP profile can act as a wireless remote control. Can be used in conjunction with A2DP or VDPT profiles.

BIP (Basic Imaging Profile) - provides the ability to transmit, receive and view images. For example, it allows you to transfer digital photos from a digital camera to the memory of a mobile phone.

BPP (Basic Printing Profile) is a basic printing profile that provides the transfer of various objects (text messages, business cards, images, etc.) for output on a printing device.

DUN (Dial-up Networking Profile) - connects a PC or other device to the Internet via a mobile phone, which in this case acts as an external modem.

FAX (Fax Profile) - allows you to use an external device (mobile phone or MFP with a fax module) to receive and send fax messages from a PC.

FTP (File Transfer Profile) - provides file transfer, as well as access to the file system of the connected device. A standard set of commands allows you to navigate the hierarchical structure of the logical drive of a connected device, as well as copy and delete files.

GAVDP (General Audio/Video Distribution Profile) - ensures the transmission of audio and video streams from the signal source to the playback device. It is basic for A2DP and VDP profiles.

HFP (Hands-Free Profile) - provides connection of hands-free car devices to a mobile phone for voice communication.

HID (Human Interface Device Profile) - describes protocols and methods for connecting wireless input devices (mice, keyboards, joysticks, remote controls, etc.) to a PC.

HSP (Headset Profile) - allows you to connect a wireless headset to a mobile phone or other device. In addition to transmitting the audio stream, functions such as dialing, answering an incoming call, ending a call and adjusting the volume are provided.

OPP (Object Push Profile) - a basic profile for sending objects (images, business cards, etc.). For example, you can transfer a list of contacts from one mobile phone to another or a photo from a smartphone to a PC. Unlike FTP, the OPP profile does not provide access to the file system of the connected device.

PAN (Personal Area Networking Profile) - allows you to combine two or more devices into a local network. In this way, you can connect several PCs to one with Internet access. In addition, this profile provides remote access to a PC that acts as a master device.

SYNC (Synchronization Profile) - used in conjunction with the basic GOEP profile and synchronizes personal data (diary, contact list, etc.) between two devices (for example, a desktop PC and a mobile phone).

The audio parameters are determined by the so-called “profiles” and the codecs used.

Bluetooth profiles for sound:

HSP (Headset Profile) - a basic profile focused only on voice transmission. Bandwidth is limited to 64 Kbps and only mono signal is allowed. Invented for use in wireless headsets. Uses CVSD audio coding, which is sufficient for intelligible speech transmission and is very resistant to transmission errors. Deeper
HFP (Hands-Free Profile) - profile for use in car headsets. The same encoding is used as in HSP. The result is mono sound with very limited bandwidth. Supports only additional device control commands.
A2DP (Advanced Audio Distribution Profile). This profile can transmit stereo sound and compress it using algorithms that are more optimal for transmitting an audio signal. You can't do without compression, because... Bluetooth bandwidth is not enough to transmit high-quality two-channel audio.

A family of proprietary protocols (Developed by CSR) solving the problem of the lack of Bluetooth bandwidth for transmitting high-quality audio signals.
Due to the encoding technology used, audio transmission is possible almost losslessly with sampling rates up to 24 bit/96 kHz. There is only one condition: AptX must be supported by both the transmitter and receiver.
The best wireless audio quality is provided by the A2DP profile in combination with the AptX family of protocols.

I just plugged the adapter into the connector of the system unit and the drivers automatically pulled up. I have windows 7:





Next I connected the column:






Adapter in socket:

Inside the adapter there is a blue LED that blinks when in use. however, it is worth noting that it is located inside the case, as if illuminating it from the inside, so it does not dazzle even at night:

Since the drivers for the device are quite old, you need to update them.

There is a developer’s website on the insert where you can download drivers:

Downloaded archive:


You need to run the exe file:













Next, connect the column again:


Even the icons have changed:



That's all, you can use:


Driver version:

The data transfer speed declared by the manufacturer is 3Mbps. The maximum range of the module is 20 meters.

In real conditions, my speaker plays within two rooms without problems; if I go to the end of the apartment or onto the balcony behind 3 walls, the music starts to be interrupted.

The ORICO BTA-403 Mini adapter copes with its functions well, the sound of the speaker is excellent without any foreign impurities.

Low price
+ Supports most modern Bluetooth protocols
+ Neat design, no bright external LED indicators
+ Software installer in Russian, software available on the Internet
+ Possibility to choose one of 4 colors

I'm planning to buy +31 Add to favorites I liked the review +30 +58

Bluetooth 5.0 became a reality. Compared to Bluetooth 4.0, the new version has twice the capacity, four times the range and a number of other improvements. Let's look at the advantages of Bluetooth 5.0 over its predecessors, including an example CPU CC2640R2F from Texas Instruments.

The popularity of the Bluetooth 4 protocol version, as well as some of its limitations, became the reasons for the creation of the next Bluetooth 5 specification. The developers set themselves a number of goals: expanding the range, increasing the throughput when sending broadcast packets, improving noise immunity, and so on.

Now that the first devices with Bluetooth 5 have begun to appear, users and developers rightly have questions: which of the previously stated promises have become reality? How much have the range and data transfer speed increased? How did this affect consumption levels? How has the approach to generating broadcast packets changed? What improvements have been made to improve noise immunity? And, of course, the main question is - is there backward compatibility between Bluetooth 5 and Bluetooth 4? Let's answer these and some other questions and consider the main advantages of Bluetooth 5.0 over its predecessors, including using the example of a real processor with Bluetooth 5.0 support produced by the company Texas Instruments.

Let's start our review of Bluetooth 5.0 by answering the most frequently asked question about backward compatibility with Bluetooth 4.x

Is Bluetooth 5.0 backwards compatible with Bluetooth 4.x?

Yes, it does. Bluetooth 5 adopts most of the features and extensions of Bluetooth 4.1 and 4.2. For example, Bluetooth 5 devices retain all the data security improvements of Bluetooth 4.2 and support the LE Data Length Extension. It is worth recalling that thanks to the LE Data Length Extension, starting with Bluetooth 4.2, the size of the data packet (packet data unit, PDU) during an established connection can be increased from 27 to 251 bytes, which allows you to increase the data exchange speed by 2.5 times.

Due to the large number of differences between protocol versions, the traditional mechanism for negotiating parameters between devices when establishing connections is retained. This means that before they start exchanging data, the devices “get to know each other” and determine the maximum frequency of data transmission, the length of messages, and so on. In this case, Bluetooth 4.0 parameters are used by default. The transition to Bluetooth 5 parameters occurs only if, during the pairing process, it turns out that both devices support a later version of the protocol.

Speaking of tools that are already available to developers, it is worth noting the new CC2640R2F processor and the free BLE5-Stack from Texas Instruments. To the delight of the developers, BLE5-Stack is based on the previous version of BLE-Stack, and changes in its use only affected the new features of Bluetooth 5.0.

How has the data transfer speed increased in Bluetooth 5?

Bluetooth 5 uses a wireless connection with physical data transfer rates of up to 2 Mbps, which is twice as fast as Bluetooth 4.x. It is worth noting here that the effective data exchange rate depends not only on the physical throughput of the transmission channel, but also on the ratio of service and useful information in the packet, as well as on the associated “overhead” costs, for example, time loss between packets (Table 1).

Table 1. Communication speed for different versionsBluetooth

In versions Bluetooth 4.0 and 4.1, the physical bandwidth of the channel was 1 Mbit/s, which, with a PDU data packet length of 27 bytes, made it possible to achieve exchange rates of up to 305 kbit/s. Bluetooth 4.2 introduced the LE Data Length Extension. Thanks to it, after establishing a connection between devices, it became possible to increase the packet length to 251 bytes, which led to an increase in data exchange speed by 2.5 times - up to 780 kbit/s.

Bluetooth version 5 retains support for LE Data Length Extension, which, together with an increase in physical throughput to 2 Mbit/s, allows data exchange speeds of up to 1.4 Mbit/s to be achieved.

As practice shows, such acceleration of data transfer is not the limit. For example, the CC2640R2F wireless microcontroller is capable of operating at speeds up to 5 Mbps.

It is worth mentioning the common misconception that the increase in throughput to 2 Mbit/s was achieved by reducing the range. Of course, physically the transceiver chip (PHY) when operating at a frequency of 2 Mbit/s has 5 dBm less sensitivity than when operating at a frequency of 1 Mbit/s. However, in addition to sensitivity, there are other factors that contribute to increasing the range, for example, the transition to data encoding. For this reason, all other things being equal, Bluetooth 5 turns out to be more reliable and has a longer range compared to Bluetooth 4.0. This is discussed in detail in one of the following sections of the article.

How to enable high speed data transfer mode in Bluetooth 5?

When establishing a connection between two Bluetooth devices, Bluetooth 4.0 settings are initially used. This means that at the first stage the devices exchange data at a speed of 1 Mbit/s. Once the connection is established, the Bluetooth 5.0-enabled master can begin the PHY Update Procedure, the goal of which is to establish a maximum speed of 2 Mbps. This operation will only succeed if the slave also supports Bluetooth 5.0. Otherwise, the speed remains at 1 Mbps.

For developers who have previously used the Texas Instruments BLE-Stack, the good news is that the new BLE5-Stack provides a single function, HCI_LE_SetDefaultPhyCmd(), to perform this procedure. Thus, when switching to Bluetooth 5.0, users of TI products will not have problems with the initial initialization. Also useful for developers will be an example posted on the GitHub portal, which allows you to evaluate the operation of two CC2640R2F microcontrollers operating as part of CC2640R2 LaunchPads in High Speed ​​and Long Range modes.

How has the range of Bluetooth 5 increased?

The Bluetooth 5.0 specification states that the range is four times greater than Bluetooth 4.0. This is a rather subtle issue that is worth dwelling on in more detail.

Firstly, the concept of “four times” is relative and is not tied to a specific range in meters or kilometers. The fact is that the radio transmission range strongly depends on a number of factors: the state of the environment, the level of interference, the number of simultaneously transmitting devices, and so on. As a result, not a single manufacturer, as well as the developer of the Bluetooth SIG standard itself, provides specific values. The increase in range is measured in comparison with Bluetooth 4.0.

For further analysis, it is necessary to perform some mathematical calculations and estimate the radio channel power budget. When using logarithmic values, the radio channel budget (dB) is equal to the difference between the transmitter power (dBm) and the receiver sensitivity (dBm):

Radio channel budget = powerT X(dBm) – sensitivityR X(dBm)

For Bluetooth 4.0, the standard receiver sensitivity is -93 dBm. If we assume the transmitter power is 0 dBm, then the budget is 93 dB.

Quadrupling the range would require a 12 dB increase in budget, resulting in a value of 105 dB. How is this value supposed to be achieved? There are two ways:

  • increasing transmitter power;
  • increasing the sensitivity of receivers.

If you follow the first path and increase the transmitter power, this will inevitably cause an increase in consumption. For example, for the CC2640R2F, switching to an output power of 5 dBm leads to an increase in current consumption to 9 mA (Figure 1). At 10 dBm the current will increase to 20 mA. This approach is not attractive for most battery-powered wireless devices and is not always suitable for IoT, which is the area that Bluetooth 5.0 was primarily aimed at. For this reason, the second solution seems preferable.

To increase the sensitivity of the receiver, two methods are proposed:

  • reduction in transmission speed;
  • use of Coded PHY data encoding.

Reducing the data rate by a factor of eight theoretically increases receiver sensitivity by 9 dB. Thus, the desired value is only 3 dB short.

The required 3 dB can be achieved using additional Coded PHY coding. Previously, in Bluetooth 4.x versions, the bit encoding was unambiguous 1:1. This means that the data stream was directly sent to the differential demodulator. In Bluetooth 5.0, when using Coded PHY, there are two additional transmission formats:

  • with 1:2 encoding, in which each bit of data is associated with two bits in the radio data stream. For example, a logical "1" is represented as a sequence of "10". In this case, the physical speed remains equal to 1 Mbit/s, and the real data transfer speed drops to 500 kbit/s.
  • With 1:4 encoding. For example, a logical "1" is represented by the sequence "1100". The data transfer rate is reduced to 125 kbit/s.

The described approach is called Forward Error Correction (FEC) and allows errors to be detected and corrected on the receiving side, rather than requiring packets to be retransmitted, as was the case in Bluetooth 4.0.

On paper everything looks good. It remains only to find out how these theoretical calculations correspond to reality. As an example, let's take the same microcontroller CC2640R2F. Thanks to various improvements and new Bluetooth 5.0 modulation modes, the transceiver of this processor has a sensitivity of -97 dBm at 1 Mbps and -103 dBm when using Coded PHY and 125 kbps. Thus, in the latter case, only 2 dBm is missing from the level of 105 dB.

To evaluate the range of the CC2640R2F, engineers from Texas Instruments conducted a field experiment in Oslo. At the same time, from the point of view of noise level, the environment in this experiment cannot be called “friendly”, since the business part of the city was in close proximity.

To obtain a power budget greater than 105 dB, it was decided to increase the transmitter power to 5 dBm. This allowed us to achieve an impressive final value of 108 dBm (Figure 2). When performing the experiment, the range was 1.6 km, which is a very impressive result, especially considering the minimum level of consumption of radio transmitters.

How has the approach to Bluetooth 5 broadcast messages changed?

Previously, Bluetooth 4.x used three dedicated data channels to establish connections between devices (37, 38, 39). With their help, devices found each other and exchanged service information. It was also possible to transmit broadcast data packets over them. This approach has disadvantages:

  • with a large number of active transmitters, these channels can simply be overloaded;
  • More and more devices use broadcast messages without establishing a point-to-point connection. This is especially important for the Internet of Things IoT;
  • the new Coded PHY coding system will require eight times more time to establish a connection, which will additionally load broadcast channels.

To solve these problems in Bluetooth 5.0, it was decided to move to a scheme in which data is transmitted on all 37 data channels, and service channels 37, 38, 39 are used to transmit pointers. The pointer refers to the channel over which the broadcast message will be transmitted. In this case, the data is transmitted only once. As a result, it is possible to significantly relieve the load on service channels and eliminate this bottleneck.

It is also worth noting that now the data length of a broadcast packet can reach 255 bytes instead of 6...37 bytes PDU in Bluetooth 4.x. This is extremely important for IoT applications, as it allows minimizing transmission overhead and eliminating connections, thereby reducing consumption.

Does Bluetooth 5 support Mesh networks?

Texas Instruments Solutions for Bluetooth 5

One of the very first microcontrollers with Bluetooth 5.0 was the high-performance CC2640R2F processor manufactured by Texas Instruments.

The CC2640R2F is built on a modern 32-bit ARM Cortex-M3 core with an operating frequency of up to 48 MHz. The operation of the radio transmitter is controlled by the second 32-bit ARM Cortex-M0 core (Figure 3). In addition, the CC2640R2F features rich digital and analog peripherals.

The advantage of the CC2640R2F microcontroller is also its low consumption level (Table 2). This applies to all operating modes. For example, in active mode, when receiving data over a radio channel, the consumption is 5.9 mA, and when transmitting - 6.1 mA (0 dBm) or 9.1 mA (5 dBm). When switching to sleep mode, the supply current drops completely to 1 µA.

The combination of three important qualities such as Bluetooth 5.0 support, low consumption and high peak performance makes the CC2640R2F a very interesting solution for the Internet of Things. At the same time, using this microcontroller, you can create the entire range of IoT devices: autonomous sensors that operate for several years on a single battery, bridges between an additional control processor and a Bluetooth 5.0 channel, complex applications that require high computing power.

Table 2. Wireless microcontroller consumptionCC2640 R2 Fwith the supportBluetooth 5

Operating mode Parameter Value (at Vcc = 3 V)
Active Computing µA/MHz ARM® Cortex®-M3 61 µA/MHz
Coremark/mA 48,5
Coremark at 48 MHz 142
Radio exchange Peak receive current, mA 5,9
Peak current during transmission, mA 6,1
Sleeping mode Sensor controller, µA/MHz 8,2
Sleep mode with RTC enabled and memory saving, mA 1

To quickly get started with the CC2640R2F, Texas Instruments has prepared a traditional development kit (Figure 4). Using a couple of such devices, you can evaluate the speed and range of radio transmission via Bluetooth 5.0. To do this, you can use ready-made examples or create your own application based on the free BLE 5 stack 1.0 protocol (www.ti.com/ble).

Conclusion

The new version of the Bluetooth 5.0 protocol is focused on maximum compliance with the needs of the Internet of Things (IoT). Compared to Bluetooth 4.0, it has a number of qualitative improvements:

  • data transfer speed has doubled and reached 2 Mbit/s;
  • transmission range has quadrupled due to Coded PHY and Forward Error Correction (FEC) data encoding;
  • Broadcast message throughput increased 8 times.

In addition, Bluetooth 5.0 provides backward compatibility with Bluetooth 4.x devices, and also supports most of the extensions of later versions of the protocol.

You can evaluate the capabilities of Bluetooth 5.0 now using tools produced by Texas Instruments. The company produces a high-performance and low-power microcontroller CC2640R2F, provides a free BLE 5 stack 1.0 and many ready-made examples for the LAUNCHXL-CC2640R2 debugging kit.

Literature

  1. Bluetooth Core Specification 5.0 FAQ. 2016. Bluetooth SIG.