High Penetration Wireless System (HPWS?)
AKCP is an engineering driven company, with a passion for technology, providing workable solutions for customers monitoring needs. Over the past 10 years we have explored and developed several wireless sensor technologies, but none of these were ever brought to market as we lacked confidence in their ability to provide a reliable solution for our customers.
AKCP have been developing products that utilize Semtech’s LoRa? radio technology with an aim to be a full solution provider for private LoRa? networks, with gateways, sensors and software. No cloud service required, keep control of your own data. By supplying both the sensors, gateways and software we have been able to deviate from the standard LoRaWAN? specifications and improve it making a High Penetration Wireless System (HPWS?). These improvements include the following :-
Listen Before Talk. LoRa? is not a full Duplex radio and only one sensor can broadcast at a time. If two broadcast at the same time, packets get muddled and the message is lost. On our sensors we have implemented a listen before talk protocol. This makes sure there are no other sensors broadcasting on this frequency before we send our message, which minimizes packet collisions increasing the reliability of packets delivered and battery life.
Acknowledgment of Messages. Standard LoRaWAN? doesn’t acknowledge the delivery of messages to the gateway. The sensor broadcasts, and once it’s done this, the message is gone. If the gateway doesn’t receive it for some reason (packet collision, out of range, powered down etc) that message and data is lost forever. This is not acceptable, particularly in mission critical monitoring systems. We have therefore implemented acknowledgment procedures. After our sensor broadcasts, the gateway has a window of opportunity in which to receive and acknowledge this message. If it does not, then the sensor will keep the data on record until it’s next broadcast interval. When this internal comes around we broadcast all the new data, plus any queued messages that were not yet acknowledged. In other words, our sensors are intelligent as well, not dumb sensors that broadcast and forget.
Sensor Thresholds. Standard LoRaWAN? wait for the sensor to broadcast, for example. you setup the sensor to broadcast once every 5 minutes, what if the temperature in your rack goes critical, and the sensor broadcast 1 minute ago? You need to wait 4 minutes before you will get the updated sensor value. Not with AKCP! We store the thresholds onboard the sensor itself. The sensor is constantly monitoring, every second, and we broadcast immediately when a sensor threshold is exceeded. This message must be acknowledged to ensure it was delivered.
For more information visit www.akcp.com