**7.5 Noise**

The noise of a coil-less fluxgate is rather high. For instance, in (Butta et al., 2010c) a coil-less fluxgate is presented which shows 3 nT/√Hz at 1Hz noise. This is much higher than the noise of other orthogonal fluxgates, operated in a fundamental mode, mainly because of low sensitivity. The noise of coil-less fluxgates manufactured with Co-base magnetic wires, which have larger sensitivity, has still not been reported. It can be expected that further improvements of the sensitivity of coil-less fluxgates will contribute to decrease the noise.
