I do understand the mathematics behind digital beamforming but I am not sure how such systems are practically implemented. For example, in a typical wideband FMCW radar operating in S-band, the (baseband) pulse bandwidth can be as large as 500MHz. To digitize this signal, you need high-speed ADCs, typically 1GHz sampling frequency. As far as I know, these ADCs are not cheap.

Now, if you have let's say a Uniform Rectangular Array (URA) with 20 antenna elements, you need to replicate your RF frontend 20 times! This RF frontend typically will include an LNA, a mixer and the high-speed ADC.

In addition, the sheer amount of data produced by the above system is huge requiring large memory and processing power.

My questions are thus:

1. Does the above scenario reflect how practical beamforming systems are implemented or is it too naive? am I missing something fundamental here?
2. Are there any hardware/signal processing tricks that can help reduce the hardware or processing requirements in such systems?

Thanks