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. © 2019 IEEE.