13.6.1 System Weight and Power

The weight and power of the radiometers have already been discussed in Section 13.3.3. Another important resource driver is the antenna reflector. Low-weight structures have been built, and it is known that a 2-m carbon fiber composite dish weighing 12 kg has been launched into space. Similarly, a 3-m dish for a future ocean salinity mission has been designed with a weight of 21 kg. So, a present rule of thumb states an antenna reflector weight around 3 to 4 kg per square meter with proven technology. Hence, the present reflector would weigh around 3 kg. With this low reflector weight, the struts and other structure to carry the reflector and the associated feeds become a significant part of the total antenna weight, in the present case around 5 kg.

Finally, a complete radiometer system of course includes several other units than what have been discussed above, and a total power and weight budget could look as it does in Table 13.11.

13.6.2 Data Rate

The data rate can be estimated by assuming 16-bit data words...