The wireless underwater communication has many civil and military applications and the interest in this field has grown over the last decades. Wireless signal transmission enables the communication with autonomous underwater vehicles (AUV) and roboter. Furthermore, with the help of wireless communication the oceans can get surveyed and monitored.
Another application is the underwater telephone, which enables the communication with and in between submarines and divers. The conventional techniques for wireless, terrestrial communications cannot be used for the signal transmission underwater, because water as a transmission medium has different characteristics to air. High attenuation and non-linearity’s like the Doppler effect, multipath-propagation and rising underwater noise leads to a severe decrease in transmission quality, in particular over big distances. The general technique for communication with submarines has not changed much since the second world war.
The recent research tries to improve the signal quality and signal range while complying with the NATO-standards.