Patent ID: 7928832

Claim:
A method of operating a first RFID read/write device and at least one second RFID read/write device, the method comprising: providing the first and second RFID read/write devices respectively comprising an RF part and a baseband part, the baseband part including a signal processor, wherein the first and second RFID read/write devices are arranged at a usable wireless transmission distance from one another; generating a reader service signal in its baseband form in the signal processor and combining the reader service signal with an RFID signal in its baseband form comprising a carrier signal, so that the RFID signal has the reader service signal modulated or embedded to it in amplitude, frequency or phase; shifting the RFID signal with the reader service signal into an RF band and transmitting the RFID signal as a transmission signal wirelessly by the RFID read/write devices; receiving the transmission signal from the first RFID read/write device by a number of electronic tags for the purpose of communicating with the first RFID read/write device; and simultaneously receiving the transmission signal from the first RFID read/write device at least by the one second RFID read/write device for the purpose of communicating with the first RFID read/write device through the reader service signal; wherein the reader service signal is arranged in the frequency spectrum as sidebands for amplitude modulation or single sideband modulation of the carrier signal; and wherein the reader service signal contains components in the spectrum in the form of amplitude modulation of the carrier signal to permit filtering of a DC component.