To improve the transmit power and receive sensitivity
- Use an antenna with more gain.
- Use the appropriate antenna for the used frequency band. The band is dependent on the telco and thus on the SIM installed.
Please note that at OWL-LTE the Mobile WAN Network type can be changed from LTE to UMTS or vcvs. and thus the frequency range might change at some telcos forcing a different antenna to be mounted. - To increase sensitivity you can mount a diversity antenna, placed a bit apart from the main antenna.