>High power radio bandpass filters allow for guard bands on the scale of a single mhz. Not at 4GHz. This stuff works in terms of percentages of the frequency i

>High power radio bandpass filters allow for guard bands on the scale of a single mhz. Not at 4GHz. This stuff works in terms of percentages of the frequency in use. The higher the frequency the larger the guard bands required for any sort of practical filtering.