Abstract: A method of temperature and/or composition measurement of an at least partially aqueous target (6) using a system (1) including; a transmitter and receiver mechanism (2) including one or more transmitting (3) and receiving antenna(e) (4); signal processing means (5), capable of calculating the attenuation of the transmitted signal; said method including; irradiating a target (6) irradiating said target with a plurality of electromagnetic radiation signals including at least a first and a second electromagnetic radiation signal of differing frequencies wherein said first signal has a frequency in the microwave/UHF spectrum, and said second signal has a frequency in the radio frequency (RF) spectrum; receiving an attenuated signal transmitted though the target (6); calculating the attenuation of the transmitted signal with said signal processing means (5).