Wireless signal

Hello,
I own 2 homes on the same property. I have my broadband internet connection set up in the front house and usually use my laptop with wireless connectivity. I have recently moved to the back house, but my modem and internet connection remains in the front home. I am finding my wireless connection is not reliable. Sometimes it is excellent and other times it has limited or no access. At this stage I am not looking at moving my internet connection to the back house. Is there anyway of boosting the signal strength so that I do not encounter this problem?

Thanks