Methods and apparatus for RFID tag communications

摘要

The present invention provides backscatter interrogators, communication systems and backscatter communication methods. According to one aspect of the present invention, a backscatter interrogator includes a data path configured to communicate a data signal; a signal generator configured to generate a carrier signal; and a modulator coupled with the data path and the signal generator, the modulator being configured to spread the data signal to define a spread data signal and amplitude modulate the carrier signal using the spread data signal, the modulator being further configured to phase modulate the carrier signal.

主权项

1. An interrogator comprising:
a data path configured to communicate a data signal; a signal generator configured to generate a carrier signal; and a modulator coupled with the data path and the signal generator, the modulator being configured to spread the data signal to define a spread data signal and to both amplitude modulate and phase modulate the carrier signal using the spread data signal before communication of the carrier signal; wherein the modulator is configured to phase modulate the carrier signal by selectively inverting the phase of the carrier signal using the spread data signal; wherein the modulator is further configured to band limit the inverted spread data signal; and wherein the modulator is configured to invert the spread data signal responsive to the spread data signal being a predetermined value.