Abstract: An RFID tag verifier includes an RF interrogator that transmits a first and second interrogation signal each having a first operational characteristic that differs from the other by a known amount. The RF interrogator receives a first and second return signal corresponding to the respective interrogation signals. A processor determines a response of the RFID tag as defined by a second operational characteristic of the first and second return signals. The verifier can determine the signal strength of the return signal for varying strengths of the interrogation signal. Typically, a flat response is desired Additionally, or alternatively, the verifier can determine the response in terms of signal strength of the response signals for interrogation signals having different frequencies. In some applications frequency selectivity may be desirable. Additionally, or alternatively, the verifier can determine the response in terms of frequency for interrogation signals having varying strengths.

Abstract: An RFID tag verifier includes an RF interrogator that transmits a first and second interrogation signal each having a first operational characteristic that differs from the other by a known amount. The RF interrogator receives a first and second return signal corresponding to the respective interrogation signals. A processor determines a response of the RFID tag as defined by a second operational characteristic of the first and second return signals. The verifier can determine the signal strength of the return signal for varying strengths of the interrogation signal. Typically, a flat response is desired Additionally, or alternatively, the verifier can determine the response in terms of signal strength of the response signals for interrogation signals having different frequencies. In some applications frequency selectivity may be desirable. Additionally, or alternatively, the verifier can determine the response in terms of frequency for interrogation signals having varying strengths.

Abstract: One or more reading devices are disposed within a hollow case sized and shaped to be held in a user's hand. A supplemental switch is also disposed in the case and is manually activatable by a user, such as by the user's thumb. Logic disposed in the case is connected to a reading device and the supplemental switch for taking a first action when the switch is activated and taking a second action when it is not. The first and second actions may comprise first and second modes of operation of the reading device. When two or more reading devices are provided, the first and second actions may include reading operations of the first and second devices, respectively. Types of reading devices that may be incorporated into embodiments of the invention include bar code scanners, RF ID interrogators, and smart card scanners.