A filter assembly comprising (a) a housing having a first housing end, a housing body, and a second housing end, the housing containing a generally cylindrical filter comprising a porous filter element, wherein at least the first housing end comprises a removable cover and a first housing end body, wherein the housing is arranged to provide a fluid flow path through the filter, such that fluid is filtered as it passes through the porous filter element; (i) the filter comprising a first end cap and a second end cap, and the porous filter element comprising a first filter end and a second filter end, the first end cap sealed to the first filter end, and the second end cap sealed to the second filter end; (ii) an RFID tag secured on, or near, the first end cap or the second end cap; (iii) a first antenna, arranged in or on the housing body; (iv) a second antenna, arranged in or on the removable cover, wherein the first antenna and the second antenna are generally coaxially arranged and separated by a gap such that the first antenna and the second antenna are inductively coupled, allowing a wireless signal to pass therebetween; (v) a third antenna, arranged in or on the first housing end body, wherein the third antenna is spaced from the RFID tag, and the third antenna is arranged to wirelessly send a signal to, and wirelessly receive a signal from, the RFID tag; (vi) an RFID signal generator/controller; and, (vii) a first cable, having a first cable first end and a first cable second end, wherein the first cable first end is coupled to the second antenna, and the first cable second end is coupled to the third antenna; wherein the filter assembly is arranged to allow a signal to pass from the RFID signal generator/controller to the RFID tag via the first antenna, second antenna, and the third antenna, and to allow a signal to pass from the RFID tag to the RFID signal generator/controller, via the third antenna, the second antenna, and the first antenna. (a) a housing having a first housing end, a housing body, and a second housing end, the housing containing a generally cylindrical filter comprising a porous filter element, wherein at least the first housing end comprises a removable cover and a first housing end body, wherein the housing is arranged to provide a fluid flow path through the filter, such that fluid is filtered as it passes through the porous filter element; (i) the filter comprising a first end cap and a second end cap, and the porous filter element comprising a first filter end and a second filter end, the first end cap sealed to the first filter end, and the second end cap sealed to the second filter end; (ii) an RFID tag secured on, or near, the first end cap or the second end cap; (iii) a first antenna, arranged in or on the housing body; (iv) a second antenna, arranged in or on the removable cover, wherein the first antenna and the second antenna are generally coaxially arranged and separated by a gap such that the first antenna and the second antenna are inductively coupled, allowing a wireless signal to pass therebetween; (v) a third antenna, arranged in or on the first housing end body, wherein the third antenna is spaced from the RFID tag, and the third antenna is arranged to wirelessly send a signal to, and wirelessly receive a signal from, the RFID tag; (vi) an RFID signal generator/controller; and, (vii) a first cable, having a first cable first end and a first cable second end, wherein the first cable first end is coupled to the second antenna, and the first cable second end is coupled to the third antenna; wherein the filter assembly is arranged to allow a signal to pass from the RFID signal generator/controller to the RFID tag via the first antenna, second antenna, and the third antenna, and to allow a signal to pass from the RFID tag to the RFID signal generator/controller, via the third antenna, the second antenna, and the first antenna. (i) the filter comprising a first end cap and a second end cap, and the porous filter element comprising a first filter end and a second filter end, the first end cap sealed to the first filter end, and the second end cap sealed to the second filter end; (ii) an RFID tag secured on, or near, the first end cap or the second end cap; (iii) a first antenna, arranged in or on the housing body; (iv) a second antenna, arranged in or on the removable cover, wherein the first antenna and the second antenna are generally coaxially arranged and separated by a gap such that the first antenna and the second antenna are inductively coupled, allowing a wireless signal to pass therebetween; (v) a third antenna, arranged in or on the first housing end body, wherein the third antenna is spaced from the RFID tag, and the third antenna is arranged to wirelessly send a signal to, and wirelessly receive a signal from, the RFID tag; (vi) an RFID signal generator/controller; and, (vii) a first cable, having a first cable first end and a first cable second end, wherein the first cable first end is coupled to the second antenna, and the first cable second end is coupled to the third antenna;