Hello.
I would like to mention that there are various ways to increase the quality factor for various system designs. First you need to specify for what application you are designing your system.
As mentioned by Mr Umer you can increase power to increase the quality factor but it has has an adverse effect on the channel as non linearities come into play but you can increase the transmission power.
I would provide you some links which you could refer to. I hope these will help.
Thanks
http://www.ijltet.org/wp-content/uploads/2013/08/4.pdf