This letter aims to study a multiantenna tag on a UHF RFID system. Impact of dual antenna on the read range is demonstrated. This letter shows that this enhancement is not only due to a better antenna gain, but also to the design of the backscattering system. Indeed, the backscattering modulator is connected on only one of the two inputs of the antenna. Measurements of prototypes designed in 0.18 CMOS process demonstrate that a tag with such a system stays visible for the reader around 2 m better than a one-antenna system.