There's a few things you can try to boost your wifi signal, starting with the least labor intensive.
If your Pulse is in a metal lined tent you can place the Pulse closer to a gap or window in the lining.
If your tent has "windows" open the window, and cover it with a dark fabric. WiFi makes it through fabric.
You can buy a simple range extender such as this one and place it close to your tent or grow space.
You can buy a router and some ethernet cable, connect it to your existing router with the cable, and set the new router in the grow space.