New Bluetooth Range Extender

Nordic Semiconductor, the manufacturer of the System on a Chip (SoC) inside most beacons, has announced a new Bluetooth Range Extender the nRF21540.

It’s an electronic component to be used at the SoC output to amplify the signal prior to being sent to the antenna. We expect this to be included in some future long range beacon designs. However, note that it uses more current (115 mA at +20 dBm) so is less suitable for use in coin-cell based battery powered designs.

Our ultra long range beacons already use RF amplifiers but from different component manufacturers. For example the iB003N-PA uses a RFAXIS X2401C chip to achieve up to 300m range. The FSC-BP109 also uses an output amplifier to reach up to 1000m on Android and 4000m on iOS but this beacon requires USB power.

nRF Connect Features

Nordic, the manufacturer of the System on a Chip (SoC) in most beacons, has a new blog post on Five Things You Didn’t Know About Nordic’s Mobile Development Apps. The post mentions less visible features of nRF Connect on iOS and Android. For example, you can get a useful RSSI graph by dragging the screen towards the right from the centre:

nRF Connect is the main app we recommend for testing beacons. iOS recently received a completely new version. nRF Connect also has macros that can speed up testing.

Latest Nordic Wireless Quarter Magazine Available

Nordic, the manufacturer of the System on a Chip (SoC) in many beacons, has the latest issue of Wireless Quarter Magazine. It showcases the many uses of Nordic SoCs.

News from the world of beacons and Bluetooth LE includes:

  • National Instruments (NI) vibration sensor enables condition monitoring of industrial plant and machinery.
  • IDC research that says commercial and consumer adoption of IoT will drive worldwide annual spending to $1.1 trillion by 2023
  • Brain cells controlled using Bluetooth LE
  • Researchers build millimeter scale Bluetooth LE antenna
  • Quuppa’s direction finding technology used for ice hockey

Nordic Wireless Quarter Magazine Available

Nordic, the manufacturer of the System on a Chip (SoC) in many beacons, has the latest issue of Wireless Quarter Magazine. It showcases the many uses of Nordic SoCs.

News from the world of beacons includes:

  • Quuppa partnership – this might accelerate Bluetooth direction finding solutions
  • Beacons helping visually impaired
  • Beacons for robot perception and interaction
  • Beacons in restaurants

How Power and Advertising Interval Affect Battery Use

Nordic Semiconductor, the manufacturer of the System on a Chip (SoC) in most beacons has a useful online calculator that helps work out the battery current used when advertising or when connected.

You need to set the SoC chip type (see the specification for the beacon you are using), voltage (3v as it’s usually a coin cell), DCDC (usually off), clock (usually external) and tx payload (set to 31 bytes). You can then vary the role (advertising or connected), power and advertising interval to see the affect on the battery current.

Dividing the battery capacity by the current will gives the approximate battery life. The resultant battery life calculation will be a very rough approximation and will be less if the manufacturer has added extra circuitry such as sensors. The online calculator is best used to get an appreciation of how changing parameters or the SoC type affects battery life rather than being a definitive value. For more accurate battery use it’s necessary to measure the actual battery current.

New Wafer Thin Nordic nRF51 SoC

Nordic, the manufacturer of the System on a Chip (SoC) found in most beacons has announced that an ultra thin version will be available from American Semiconductor.

The AS_NRF51 Flex-BLE (pdf) is an ultra-thin version of Nordic’s nRF51822 SoC wafer-level CSP (WL-CSP), employing American Semiconductor’s ‘FleX™ Semiconductor-on-Polymer™’ (FleX SoP) process to reduce package size to approximately 35µm—roughly half the thickness of a human hair.

The largest component of beacons and Bluetooth sensors is usually the battery rather than the SoC. However, the Flex-BLE version will be especially suited to energy harvested and solar solutions where it will be possible to create very thin beacons that can be invisibly manufactured into products or their packaging.

Latest Nordic Wireless Q Magazine Available

Nordic, the manufacturer of the System on a Chip (SoC) in many beacons, has a latest issue of Wireless Q Magazine. It showcases the many uses of Nordic SoCs.

Read about:

  • The Ruuvi IoT asset tracker
  • Smart rope load sensors
  • Use of SoCs in an insulin monitor device
  • A wearable respiration monitor
  • Bluetooth 5.1 direction finding
  • Tracking shipping containers
  • IoT for farmers
  • Use of SoC for athlete performance wearable
  • Building next generation Bluetooth beacons

Smart Cycling Helmet

Nordic have news of a new cycling helmet with embedded nRF52 device, also used inside many beacons, that detects acceleration and in conjunction with an app, can send location and crash alerts.

While it’s an interesting and innovative product, most of the work is done by the app. There’s no reason why a generic acceleration sensor beacon couldn’t have been used within the helmet (or elsewhere). However, we guess including anything extra inside a helmet, in a safe manner, poses some challenges.

An insight from this is that there are probably many untapped opportunities for vertical sensor beacon type applications that predominantly make use of apps to provide for much of the functionality.

What’s the Affect of Changing the Power on the iB003N-PA?

The iB003N-PA has a range up to 300m because it uses the RFAXIS X2401C 2.4GHz amplifier to increase the range.

iB003N-PA

When you use the manufacturer app to change the power output by a beacon, you are changing the power output by the Nordic nRF51 System on a Chip (SoC) that is usually fed to the antenna. In the case of the iB003N-PA, the RFAXIS X2401C instead receives the signal, amplifies it and sends it to the antenna. The resultant change in output is:

SoC Setting X2401C Output
0dbm 20dBm
4dbm 20dBm
-5dbm 15dBm
-10dbm 10dBm

20dBm is the maximum allowable output for class 1 Bluetooth. There’s no difference whether you set to 0dBm or 4dBm, the output will be 20dBm. Even at a low power setting, -10dbm, the amplified output is 10dBm which is relatively high compared to the nominal 0dBm for most beacons. That’s just over 3x the power (3dBm change is a doubling of power) of a normal beacon. You can see that this beacon is primarily designed for long distance and there’s no need to change the SoC power from the default 0dBm = 20dBm.

View our ultra long range beacons

Inside a Beacon – Part 3 – Programming the SoC

Part 1 Part2

This is part 3 of a 3 part series that explains what’s inside a beacon. In this part we take a look at the System on a Chip (SoC) software and programming for the Nordic nRF range found in the majority of beacons.

Despite the small size and memory, a typical beacon contains lots of code written in the c programming language. The code required to implement Bluetooth, called the Bluetooth stack, is very complex. It also has to pass tests by the Bluetooth SIG, called qualification. To prevent every product vendor using the SoC having to write the Bluetooth part themselves, Nordic supply what’s called a SoftDevice. A SoftDevice is a precompiled and linked binary library implementing a wireless protocol, Bluetooth in our case.

For the nRF52, the S132 SoftDevice provides a qualified Bluetooth® 5 low energy (BLE) Central and Peripheral protocol stack solution. It provides eight connections with an Observer and a Broadcaster role all running concurrently. Use of a softdevice allows developers to concentrate on their own high level product functionality rather than lower level complexities.

Beacon manufacturers or 3rd party developers such as ourselves create a program using either SEGGER Embedded Studio (SES), MDK-ARM Keil µVision, GNU/GCC or IAR Workbench. Most development now uses SEGGER Embedded Studio because Nordic have licensed it to allow Nordic developers to use free of charge. Most Nordic code examples in the nRF52 SDK now include a SEGGER Embedded Studio project file.

There are two ways of programming, either pre-programming the SoC with production code before mounting using socket programming or programming the SoC after mounting in the circuit. The PCB holes mentioned in part 1 are used to program the beacon in the circuit. A jig with pogo pins (pins with springs) can be used to help programming larger number of devices:

Jig in use at BeaconZone

The other end plugs into a nRF52 DK that has a debug out header at the top right:

If you keep the pins connected to your beacon, you can run and debug the code, in situ, via the SEGGER IDE. However, debugging is not that capable because it’s not possible to continue from breakpoints. You have to re-run or rely on lots of logging to the console.

The nRF52 DK also contains a nRF52 which means it can be used in the initial stages of product development prior to moving to actual hardware.