Help to create a network of distributive sensors

Hi…

I have experience on algorithm development and nonlinear control design, but now I have to work with networks of low cost sensors in order to develop some new data fusion ideas, and I don’t have any experience on hardware stuff (literally…no experience… nothing ;-( ):

I need to create a structure to integrate different types of sensors with the following properties:

1.- Each sensor will need its own battery and network connectivity to send its data (wifi network?), that is, the sensors will be installed on different types of vehicles and positions without any wired connection.
2.- Initially a sensor must include a IMU + GPS, but in the future I need to integrate individual radar, sonar, termal, humidity, … a collection of other types of sensors (initially we also need an independement GPS + RTK sensor with high precision to be connected to the network)
3.- I will use a centralized hardware to receive and save data acting as a sensor network server.
4.- It is possible that some sensors must store it’s own data because its localization does not allow wifi type connections.
5.- Some sensors will be installed on a maritime enviroment, with high level of corrosion.

I don’t know if such general specifications are enough to help me solve my doubts:
1.- What sensors do you recomend for the GPS+ IMU and the GPS + RTK.
2.- What type of batery shoul I use?
3.- I think on a wifi network, but maybe there are better alternatives. Unfortunately I don’t know the good questions to be done in this scope!!
4.- What type of network connectivity should I use?
5.- Raperry or arduino for the central server?

And the mos important: waht other laboratory material should I need to start the construction of the first sensors with IMU + GPS?

Thanks in advance for the support !!!