The world has been moving to wireless, rather than wires, for some years. But the move has picked up further momentum recently, driven by the perceived needs of the Internet of Things (IoT).
The Cover Story in the 25 November 2014 issue of New Electronics took a look at home automation aspects of the IoT, concluding that the communications protocols currently in use may not be suitable for future applications. The race is on, one industry expert concluded, to develop more applicable protocols. For the moment, however, many industrial wireless communication schemes are based on the unlicensed 2.4GHz Industrial, Scientific and Medical (ISM) part of the spectrum, where standards such as Wi-Fi and Bluetooth are amongst the most popular. But attention is also turning to another ISM band, centred on 868MHz in Europe and 915MHz in the Americas. While other communication protocols are available, one of the main focuses is Bluetooth. CSR and Laird announced the BT900 series of Bluetooth 4.0 dual mode modules at electronica in November. Based on the CSR881 platform, the modules are said to be targeted at those OEMS looking to support connection to legacy devices. "The BT900 series has been designed specifically to meet OEM needs for high performance and low cost," said Laird's product director Jonathan Kaye. "The modules offer a flexible solution that caters to a range of applications, from medical peripherals to point of sale terminals and barcode scanners." Laird has combined the CSR8811 platform with an ARM Cortex-M3 MCU. Laird's smartBASIC solution acts as a bridge between software and hardware, allowing an application written for one smartBASIC radio to work with any other. The Cortex-M3, meanwhile, eliminates the need for an external MCU. "We have a long standing partnership with CSR and collaborated closely to bring its Bluetooth silicon together in our module," Kaye noted. "This allows us to offer robust and innovative Bluetooth modules that are feature rich and easy to integrate." Looking to address demand for long range Bluetooth communication, Solid State Supplies is offering Bluegiga's BLE121LR extended range Bluetooth Smart module. According to the company, the module enables engineers to develop low energy applications that can communicate over distances of up to 450m, whilst benefiting from Bluetooth Smart interoperability. The module, which measures 13 x 14.7 x 1.8mm, features an integrated antenna and can be powered from a 3V coin cell. It has a receiver sensitivity of -98dBm and transmit power of 8dBm – within the maximum figure of 10dBm specified by Bluetooth Smart. Alongside the Bluetooth radio, the BLE121LR integrates an MCU, allowing the module to host user applications, as well as a Bluetooth Smart software stack and GATT based profiles. Built in flash can store application data and settings, whilst supporting field upgradeability. The BLE121LR implements Bluegiga's Bluetooth Smart Software Development Kit, in addition to the Bluetooth Smart stack. This provides users with a development environment for on board and off module applications. Microchip is continuing to broaden its technology portfolio and has launched its first Bluetooth 4.1 Low Energy module. Called the RN4020, the device features a Bluetooth Low Energy software stack and support for common low energy profiles. This, says the company, speeds time to market whilst ensuring Bluetooth compatibility. The module also comes with the Microchip Low energy Data Profile, which enables designers to stream any type of data across the link. Because the RN4020 is a stack on board module, it can connect to any MCU with a UART or operate in standalone mode for basic data collection and communication – including as a beacon or sensor. The RN4020 module – which measures 11.5 x 19.5 x 2.5mm – is said to include the hardware, software and certifications that designers need to add connectivity to any design. It also features an integral PCB antenna with a transmit power of 7dBm and a receive sensitivity of -92.5dBm, supporting communication over distances of up to 100m. But while there is growing demand for wireless connectivity at 2.4GHz, not every application is suited to Bluetooth. Catering for those instances, LPRS is offering Circuit Design's STD-503 2.4GHZ wireless transceiver for industrial applications that require stable and reliable operation. The STD-503 uses noise resistant direct sequence spread spectrum modulation to improve transmission speed and to provide a diversity receiver function, preventing signal drop out due to multipath fading. This is accomplished through the use two antennas facing in different directions. Measuring 40 x 29 x 5.5mm, the STD-503 is not only half the size of earlier designs, it also retains the same command controls used for frequency channel switching and can store up to 20 preset channels. At the chip level, Atmel has recently unveiled a new family of wireless transceivers. The AT86RF215 is a dual band device, addressing sub GHz and 2.4GHz applications. This will be followed by the AT86RF215M, a single band sub GHz transceiver, and the AT86RF215IQ, a dual band I/Q radio. "We are excited to see the widespread adoption of standards based connectivity solutions," said Kourosh Boutorabi, Atmel's senior director of smart energy products. "Expanding our portfolio to include new wireless transceivers reinforces our commitment to serve this growing market." The AT86RF215 supports a variety of data rates with three modulation schemes: multirate and multiregional frequency shift keying (MR-FSK); orthogonal frequency division multiplexing (MR-OFDM); and offset quadrature phase shift keying (MR-O-QPSK). Also addressing this market is On Semi, with the NCS3651x family of 2.4GHz SoC transceivers. The NCS3651x family supports IEEE802.15.4, including ZigBee, 6LoWPAN and WirelessHART. Pointing the application towards low data rate, intermittent IoT devices, On Semi says the SoCs include a Cortex-M3, as well as various configurations of RAM and flash memory. "Low power, robust integrated wireless communications devices will be key in helping the IoT and smart metering achieve their potential," said Ryan Cameron, VP industrial and timing products. Distributor EBV has been developing its own semiconductor solutions for the last few years. The solutions it develops are said to meet specific requirement not addressed by products already on the market. The latest addition to its portfolio is Vesta, a 900MHz wireless communications module. Dr Eckart Voskamp is director of the EBVchips programme. "Vesta is aimed at IoT3.0 applications, including smart grid, smart cities, wearable and safety," he said. "IoT3.0 is the equivalent of adding safety and security," he explained. Operating at frequencies ranging from 868 to 928MHz, the Vesta module uses the O-QPSK modulation scheme to create asynchronous mesh networks. It comes with a native IP500 protocol stack and support for IPv6, IEEE802.15.4 and 6LoWPAN. Dr Voskamp claimed the module, which features an Atmel chipset, is the first such device to be certified for use in safety applications. "We are also developing a dual wireless module, which will add 2.4GHz capability. This is currently being certified." Vesta is said by EBV to be suited to smart control and asset tracking applications, including smart buildings, low power sensor networks and wireless automation. Its generic BACnet application interface also eases integration problems.