Page 119 - 2023-Vol19-Issue2

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standardized to realizable values according to the market avail-
ability. The depicted values of the lumped elements in Fig-
ure 13 achieved the given gaols of S22 < -40 and S11 < -10
for the ±5 MHz around the operation frequency of 435 MHz.
Fig. 13. LNA schematic diagram with optimized lumped
elements
III. RESULTS
The input and output-matched transistor performance re-
sults are presented in terms of the S-parameters, the power
gain, and the NF. In Figure 14, the S11 and S22 parameters
show good magnitude values that satisfy the satellite com-
munications design requirements. Furthermore, the designed
LNA offers a power gain of about 26.149 dB at 435 MHz, as
demonstrated in Figure 15. The proposed LNA achieved a
low NF value of 0.459 at the targeted operation frequency,as
presented in Figure 16. The achieved high gain along with
the very low NF were not at the price of design complexity
since the depicted LNA design is a single stage amplifier with
proper biasing and matching networks.
Fig. 14. S-parameters of the optimized LNA
Al-Anbagi et al.
Fig. 15. Optimized LNA’s Power gain
Fig. 16. NF versus frequency for the optimized LNA
Further insight into other achievements from the literature
versus the findings of the presented work are compared in
Table II. Throughout this comparison table, we can clearly see
how the listed previous designs were subject to the tradeoff
to either achieve good gain at the price of poor NF values
or vice versa. Even when the previous LNAs achieved high
gain and an acceptable noise figure, they lacked consideration
regarding power consumption. This study offered an LNA
design capable of achieving high gain at a very low NF and
consuming considerably low power.
These achievements emphasis the novelty of this design to
not only fulfill the aspirations of the satellite communications
requirements but also meet the aim of constructing affordable
and simple amateur ground stations for small satellites.