Due to the fact that the LNA of tinySA ULTRA is only effective below 3.5GHz, some users hope to improve high-frequency sensitivity, which is very useful for users who need to measure 5.8GHz applications. We have checked some widely used modules in the market, and most of the broadband LNA modules with a nominal 6GHz have very poor flatness. Some standard 20dB LNA modules have a gain of less than 10dB at 6GHz. And these modules do not provide actual test data, only chip data manuals are provided, but most of the modules are not completely consistent with the circuits in the chip manual, which causes difficulties for users when using them in practice, especially for some cascaded modules that claim high gain. At low frequencies, there may be a risk of high gain, low k value, and self excitation damage to the receiver. For ease of use, we have designed a series of LNA modules with USB interfaces.

 

The Zeenko UM series is a USB interface powered RF low-noise amplifier launched by Zeenko, featuring a convenient power interface, moderate gain, high IP3, and low noise. This series uses a USB type-C interface for power supply, with a built-in high PSRR LDO that can effectively reduce power noise. Compared with other vendors’ USB directly fed modules, it effectively reduces background noise. The ZKxx UM series LNA adopts a very compact design and uses a system shielding cover. It may rust due to moisture, so please pay attention to moisture prevention when using it outdoors.

 

The Zeenko BM series is a USB interface powered RF low-noise amplifier with built-in battery launched by Zeenko. Adding batteries and reducing power consumption on the basis of ZKxx UM is suitable for portable use. Compared with other merchants’ built-in battery modules, it has a flatter consistent gain, lower background noise, smaller size, and longer battery life.

 

The following is the measured data of UM series LNA, you can choose according to your needs. The higher the amplifier gain, the better. As a preamplifier or antenna amplifier, it should be selected based on the post amplifier feeder loss+receiver noise figure+(3-6) dB, usually 20dB is sufficient. For the preamplifier of a spectrum analyzer, due to the wide bandwidth of the front-end circuit, the larger the gain, the worse the anti blocking performance, and the stronger the intermodulation products, making it more susceptible to interference. If there are no special requirements, please do not use both the built-in LNA and external LNA of tinySA ULTRA at the same time.

1 x Low Noise Amplifier