Range is given by the TX output power, the RX sensitivity and the antenna gain. To improve the RX sensitivity you can reduce the data rate and typically 6 dB sensitivity improving will give twice the range. When it comes to chip antenna, we experience reduced performance (typ 30% range reduction) compare to quarter wave whip. Please also be informed that you can make an antenna at 915 MHz using a simple wire or PCB track of 7.8 cm. You can try to replace your chip antenna with 7.8 cm Wire to get an indication of your chip antenna performance. We have used the 868 MHz chip antenna from Fractus in our range testing.
Last Update: August 8, 2017