For development at your own facility, the simplest solution would be a Bluetooth serial link. See
http://www.blueconsole.com/ for one option.
At a FIRST competition, the rules currently prohibit any wireless communication to/from the robot other than the provided radios. There's no practical way to send data from a laptop, but you can receive from the robot using the dashboard port. You've got six bytes of user data in the dashboard stream to work with, and you can "borrow" unused PWM outputs for telemetry information as well. The battery voltage is already provided in the dashboard data.