Wireless communication has become more popular over the last decade. Although there are many advantages to use wireless over fixed line systems, there is a major disadvantage, which is a high transmission error rate in a temporal and permanent noisy environment. There are techniques to reduce effectiveness off transmission errors in wireless communications. We have discussed in this paper. Many methods and techniques have been implementing to deal and resist errors (by increasing transmission power, switching modulation scheme) as well as evaluation the wireless connection performance taking into account many factors.