I run my Rpi using SSH or VNC.
Recently I have added agps module which is working well and I have started taking the RPi for#a walk to see how accurate the GPS is. (answer: quite accurate but not accurate enough to guarantee the robot it is intended to pilot will not go for a swim in the garden pond).
Shortly after leaving the range of the house Wifi the little blue light on my Wifi dongle stops winking and presumeably stops working.
I suspect it is intended that it does this to save power.
However back at the house and withing range of the Wifi it does not restart. This means I have no way of communicating with the RPi and have to turn the power off. This risks corrupting the SD card and loses the last few minutes of data I have been writing to file because it has not been written. (The last part has been solved by forcing the data to be written by closing the file after every write).
The question is:
How do I reawaken the Wifi?