Operating from 20 to 40 GHz, two radios may be connected to the system allowing full duplex operation. Each radio may operates over identical Air Interface with uni or bi-directional multipath. The delays between radios may be varied from 0 to 1 mile in 5 foot steps with propagation loss control. The 2040+ creates a variable test range right in your lab. It can be used as a design aid and as a test tool for new modulation and encryption schemes prior to expensive and time consuming field testing.