A Study of the Effect of DC Conditions on a 5.8 GHz Power Amplifier’s S-Parameters

Öz

This study investigates changes of S-parameters (S₂₁, S₁₁, S₂₂, S₁₂) of a SBB5089Z power amplifier module in relation to changing DC conditions. Behaviour of those linear performance parameters (S₂₁, S₁₁, S₂₂, S₁₂) was examined graphically. S-parameters of SBB5089Z were analysed covering the 5.8 GHz WiMAX frequency from 5.7 GHz to 5.9 GHz with 200 MHz bandwidth. DC conditions were controlled using a microcontroller, an R/2R Digital Analogue Converter (DAC) ladder circuit and a voltage follower with LM324. The R/2R ladder circuit and voltage follower with LM324 have been integrated with the microcontroller. Also ACS712 current sensor and ADS1115 16-bit Analog Digital Convertor (ADC) are integrated to the microcontroller. PA’s current was read with microcontroller.

Anahtar Kelimeler

• Power Amplifier,WiMAX,DC conditions,5.8 GHz,microcontroller

Besleme Koşullarının 5.8 GHz Güç Yükselteci S-Parametreleri Etkisi Üzerine Bir Çalışma

Öz

Bu çalışma, değişen DC koşullara bağlı olarak SBB5089Z güç yükselteç modülü S-parametrelerindeki (S₂₁, S₁₁, S₂₂, S₁₂) değişimleri araştırmaktadır. Doğrusal performans parametrelerinin (S₂₁, S₁₁, S₂₂, S₁₂) davranışı grafiksel olarak incelenmiştir. SBB5089Z' nin S-parametreleri, 5.8 GHz WiMAX frekansını kapsayan, 5.7 GHz'den 5.9 GHz'e kadar 200MHz bant genişliği ile analiz edilmiştir. DC koşullar, bir mikrodenetleyici, bir R/2R sayısal analog dönüştürücü merdiven devresi ve LM324’lü bir gerilim izleyici kullanılarak kontrol edilmiştir. R/2R merdiven devresi ve LM324’lü gerilim izleyici devresi mikrodenetleyici ile entegre edilmiştir. Aynı zamanda, mikrodenetleyiciye ACS712 akım sensörü ve ADS1115 16-bit analog sayısal dönüştürücü de entegre edilmiştir. Güç yükselteci akımı mikrodenetleyici ile ölçülmüştür.

Anahtar Kelimeler

• Güç Yükselteci,WiMAX,5.8 GHz,DC koşullar,Mikrodenetleyici

Kaynakça

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