Marking of Lab 6

The lab was marked out of 17; 8 marks for the specification portion and 9 marks for the design portion.

                         Specifications

Marks were assigned for correctly computing each of the following requirements:

- min/max signal level (min/max gain) (2 marks)

- carrier center frequency range (1 mark)

- NF (including BER and SNR requirements)  (3 marks)

Note that a range of values for NF were accepted if the calculations were correct and the assumptions were clearly documented.  Differences resulted from assumptions about the noise bandwidth (between 2 and 5~MHz) and implementation margin (between 1 and 10~dB).

- IIP3 based on alternate & adjacent channel rejection (2 marks)

Many students used the (incorrect) formulas in a solution from TAMU. In this case one mark was awarded for effort.

                             Design

Only the following specifications of the following components were checked to see that their specifications agreed with those used the cascade calculations (1 or 2 marks were awarded as shown below for a total of 6):

- one LNA (NF and gain, 2 marks)
- one mixer (IP3 and loss, 2 marks)
- one amplifier (gain, 1 mark)
- one filter (frequency response, 1 mark)

Because of the wide range of possible component choices and the
difficulty of checking numerical results generated by
spreadsheets, only a rough ``sanity check'' was performed on the
cascade gain, IP3 and NF results. (3 marks total were awarded for cascade
gain, NF and IIP3 calculations)