Some of the active antennas can be glued along the upper edge of the windshield.
The best reception can be achieved by limiting screening from car body and keeping it away from noisy engine ignition.
Quite often not the antenna is the main problem but bad condition of radio reception block. Many components are loosing electrical parameters which lead to improper input filter and amplifier characteristics resulting in a poor reception on any band.
Also lack of proper internal filtering can lead to instability of the power and increased internal electrical noise ending up with poor or no reception.
It was also discussed on the forum that proper supply (wire routing and filtering) has significant impact on radio reception.
Poor radio reception might also lead to poor engine grounding, worn-out ignition breaker capacitor or even improper operation of charging circuit (e.g. alternator diode failure).