Radio Transceiver simplifies wireless data transmission.
Press Release Summary:
Designed for use in USA and Europe, ER900TRS module utilizes easyRADIO(TM) software technology and has all required communications protocols embedded in onboard memory. It is capable of operation between 860-920 MHz as well as US-approved 902-928 MHz and pan-European 868-970 MHz bands. Measuring 38 x 14 x 4 mm, module integrates radio, microcontroller and power supply circuitry in 9-pin SIP that has serial input and output lines in addition to received signal strength output.
Original Press Release:
easyRADIO(TM) Transceiver Modules Make Wireless Data Transmission Simple for USA and Europe!
Pittsford, NY. ER900TRS is a new radio transceiver module that combines the revolutionary easyRADIO(TM) software technology with global applications potential. All the required communications protocols are embedded in the module's onboard memory to allow OEMs to add reliable wireless operation to their products without needing to understand radio technology.
The intelligent ER900TRS is capable of operation between 860 and 920MHz, and so is suitable for use in both the US-approved 902-928MHz band and the pan-European 868-970MHz band - so you can use the same module for USA or Europe - just make a software command change! All this comes in a 2" single-inline package that is smaller than most receivers, let alone transceivers.
easyRADIO(TM) software insures that the datastream from transmitter to receiver is efficiently packaged to maximize both the range and the data transfer rate of the radio link. The datarate of the link defaults to the industry standard of 19.2Kbit/s, but can be programmed to any rate between 2.4 and 38.4Kbit/s. All encoding/decoding functions are also handled onboard.
The new ER900TRS transceiver suits any wireless application requiring two-way data telemetry, or where a receiving node needs to confirm data reception. This includes equipment such as remote data acquisition systems, handheld terminals and electronic point of sale terminals, etc.
ER900TRS transceiver is supplied "ready-to-run out-of-the-box", but designers can customize their radio links with user-programmable functions using simple software commands. For US applications the transceiver is compliant with FCC Part 15. (Maximum power output in the US 902-920MHz band is limited to 1mW.) For European use the transceiver complies with EN300-220-3 and EN301489-3, and its transmit power output is fully programmable depending on the frequency chosen. A line-of-site range of 250m 869.85MHz or 150m at 914.5MHz is attainable using a standard 50ohm whip antenna.
Engineers often find that wireless transceiver applications can be ambitious, leading to disillusionment and frustration with radio technology. easyRADIO(TM) technology overcomes that hurdle, and - as a bonus - there is no need for designers to redesign when going to foreign markets.
ER900TRS radio transceiver has serial input and output lines to simplify interfacing with host equipment. The module also features a received signal strength output, useful when optimizing fixed links or networks of devices. The transceiver modules are designed to run from 3.6 to 5.5V, with typical current drains for transmit and receive functions of 23 and 17mA, respectively. When idle, the transceiver draws a low quiescent current of 2mA. The transceiver comes in a screened single-inline module, which integrates radio, microcontroller and power supply circuitry in a space-saving 9-pin SIP, measuring just 38 x 14 x 4mm. Operating temperature is an extended commercial range from -20 to +65 degrees C.
Made in Europe by Low Power Radio Solutions, ER900TRS is available as a $149 Starter Kit from LPRS' USA agents Saelig Co. Inc. Pittsford, NY (585-385-1750; fax - 1768; info@saelig.com). ER900TS Transmitters/ ER900RS receivers are $28/16 (100 qty).
More: Alan Lowne, 585 385-1750 o fax -1768 Saelig Co. Inc, 1160-D2 Pittsford-Victor Rd. Pittsford, NY 14534 USA. info@saelig.com
BACKGROUND:
What is 'easyRADIO'(TM)?
Before 'easyRADIO'(TM)
The market for 'ready-to-go' low power radio modules is now well established due to designers quickly realizing that the use of an approved radio module saved them many months of hard work. While the individual components required to manufacture a module may have been low cost, the practical difficulties of designing, getting approvals and then producing and testing a consistent product in high volume were both frustrating and costly in money and time.
The use of these radio modules opened many new markets as the ability to communicate data (license free) over distances of several hundred meters spurred the imagination of designers and marketers. At first the communication was 'one way' (simplex) using separate transmitters and receivers but the need for reliability and 'guaranteed delivery' required the eventual use of bi-directional (half duplex) transceivers. The 'one way' systems usually used off the shelf digital encoder and decoder ICs to provide some security. To increase the reliability of these simple systems the message was repeated multiple times. This was of little consequence for basic 'on-off' controls where the delay of sending and receiving redundant information could be tolerated.
Transceivers were usually used for more demanding 'data transfer' applications where the essence was speed. The amount and type of information sent was greatly increased (temperatures, pressures, counter values) and the mechanism generally used to provide reliability was 'acknowledgement' of messages. Long delays and redundancy could no longer be tolerated and an efficient communications 'protocol' was required to accurately deliver messages 'right first time'. The obvious choice for this task was the ubiquitous micro controller.
The challenges
The designer was now faced with a new problem whose complexity and difficulty was not immediately apparent. There were no 'off-the-shelf' solutions and industry standard protocols such as 'Ethernet' or 'CAN' were either far too complex or unsuited to specific applications. Many at first applied the simple encoding and decoding methods previously used for simplex systems and just bolted on extra 'bits' or 'bytes'! These were clumsy and grossly inefficient but at least they worked in a fashion. Others attempted to use microcontroller UARTs or 'bit bashing' to implement RS232-type communications. These were perplexingly disappointing in performance. The problem lay in not comprehending the unusual properties of these low power radio links despite the module manufacturers providing copious parametric data.
The considerations were that the link was AC coupled, limited in bandwidth (50Hz to 20KHz) and subject to interference and noise spikes. Transmitted 'pulses' would be distorted in width and edges would 'jitter' dependant upon range and would not immediately produce a clean output or even be lost whilst internal circuitry settled. When there was no signal present the data output would typically produce digital 'white noise' from which the wanted signals would suddenly appear. To compound the difficulties designers would often attempt to use their existing system microcontrollers and burden them with these very complex real time tasks.
It was therefore not surprising that many projects died, and were put in boxes under the bench in the development department never to be seen or heard of again. It was frankly - just too difficult! The module manufacturers and their distributors offered applications assistance and even wrote whole books on 'how to make it work' but often to no avail. Resourceful application engineers at Low Power Radio Solutions, (LPRS) with over ten years experience in writing encoding and decoding software for radio links, decided to do exactly 'what it says on the box' and find a Solution. The aim was to make radio easy to use with an understandable user interface that allowed data to be simply sent across the link.
Problem solved
Almost all radio modules need to be 'teamed up' with a microcontroller and initially it was thought that a general-purpose 'add-on' controller could be designed, however, different types of radios (wide band/narrow band) have widely varying parameters and some radios need to use a controller to program the transmit/receive frequencies. The 'do anything for everyone' solution looked inelegant and after several design meetings it became obvious that the controller should be 'embedded' within the radio module. The latest generation of low cost 'flash' microcontrollers made this entirely feasible. The benefits of doing this were that the core software would present a consistent interface to the user but it would be internally 'tailored' to the exact requirements of the radio. This optimization would ensure that the complete system was 'tuned' for the very best performance - even simple one-way On/Off systems would benefit from increased range, better reliability and faster speed of response.
If transmit or receive frequencies were to be programmed then this service could be provided thus relieving the user from this complex mathematical task. For some products this would also allow the configuration of frequencies used for different regions (Europe/USA). In addition, for high volume customers, the product could also be 'customized' to their requirements at modest cost. LPRS named this technology 'easyRADIO'(TM) and the first products to benefit were LPRS ER400 and 900 ranges of transmitters, receivers and transceivers covering most world markets.
The interface of host systems to low power radio transceivers had previously posed great difficulties to users as 'dumb' transceivers were particularly difficult to use and even 'intelligent' interfaces were not intuitive. 'easyRADIO'(TM) eliminated these problems by adopting 'RS232' type serial communications as the means of getting data in & out of the transceiver. The host now merely has to send & receive serial data in a standard format to and from the transceiver and there is no longer any need to understand complex transceiver parameters and all their implications. These have now all been encapsulated to provide an efficient data transport service.
The user can then concentrate their efforts on the application and be happy to know that getting data from A to B over the radio link is 'all taken care of' - 'easyRADIO'(TM)
