How do I stop my portable heater from tripping the circuit breaker?

My 1500watt portable heater keeps tripping the circuit breaker in the basement. How do I stop this from happening? The breaker runs several different outlets in the backside of the house, and the outlet on the porch where I have the heater plugged in. I thought about trying to put a bigger breaker in the box than the one thats there now which is a 15 amp. I'm also running a tv, portable stereo, microwave, coffee maker, and alarm clock all from one outlet on the porch where I spend most of my time, and sleep. There is another tennant in the basement where the breaker box is located, so if it trips at 2:00 or 3:00 in the morning, I spend the rest of the morning freezing because I don't want to disturb him from his sleep to turn the breaker back on for me. Please help!
Sincerely,
Anthony