A perishable integrity indicator system includes a RFID transponder and a perishable
integrity sensor. The RFID transponder includes a RF integrated circuit coupled with an …

Visual and audio communication interface for a perishable integrity indicator system which
includes a RFID transponder and perishable integrity sensor. A perishable integrity indica …

5,442,669 5,491.482 5,519,381 5,528.222 5,563,928 5,564,926 5,572,169 5,640,687
5,649,295 5,745,036 5,798,694 5,802,015 5,809,518 5,835,553 5,847,705 5,850,187 …

A condition monitoring system includes a radio frequency transponder module including an
RFID chip having a first memory, and an antenna; at least one sensor module that monitors …

Visual and audio communication interface for a perishable integrity indicator system which
includes a RFID transponder and perishable integrity sensor. A perishable integrity indicator …

BACKGROUND RFID or radio frequency identification technology has been used in a
variety of commercial applications such as inventory tracking and highway toll tags. In …

A communication system is provided that enables a node to be identified by a controller. To
establish a communication link from the node an alignment signal is received from the …

(57) ABSTRACT A communication system is provided that enables a node to be identified by
a controller. To establish a communication link from the node an alignment signal is …

Related US Application Data Division of application No. 1 1/781,859, filed on Jul. 23, 2007,
which is a continuation of application No. 1 1/668,922, filed on Jan. 30, 2007, now …

A modulator circuit comprises a negative impedance amplifier which is operable such that a
signal applied to the amplifier is reflected and amplified. Switching means are provided for …