  LoRaWAN has emerged as one of the promising low-power wide-area network
technologies to enable long-range sensing and monitoring applications in
Internet of Things. The LoRa physical layer used in LoRaWAN suffers from low
data rates and thus increases packet duration. In a dense LoRaWAN network
scenario with simple media access protocol like ALOHA, the packet collision
probability increases with increase in packet duration. This degrades over-all
network throughput because of increased re-transmissions of collided packets.
Any increase in data rate directly reduces the packet duration. Thus, in this
paper, we have proposed a novel approach to enhance the data rate in LoRa
communication system by using adaptive symbol periods in physical layer. To the
best of our knowledge, this is the first attempt at using adaptive symbol
periods to enhance data rate of the LoRa system. The trade-off of the proposed
approach in terms of required symbol overhead and degradation in bit error rate
performance due to symbol period reduction has also been analysed. We have
shown that for reduction factor \(\beta\), the data rate directly increases
\(1/\beta\) times.
