Consider the following statements relating to problem of mounting the bolometer in a waveguide for microwave power measurement.
1. The first requirement in the mounting is that the mount and bolometer match the impedance of the waveguide and this can completely be solved by incorporating tuning elements.
2. The operating resistance of the bolometer, determined by the point of operation may be used as one of the variables in impedance matching and is chosen to be about equal to the characteristic impedance of the waveguide.
3. Mechanically it is very difficult to ensure that the bolometer is subjected to the microwave power and at the same time arranged so that it can be connected in low frequency bridge circuit.
4. A stub and short-circuited section behind the bolometer are introduced for cancelling reflections at frequencies different from the centre frequency and thus to increase the bandwidth of the mount. Of the above statements: