At present, there are many kinds of jammers for cell phone on the market at this stage, and the quality is also uneven. Generally speaking, signal jammers can ensure the shielding of 4G/3G/2G signals of the three major operators of Standard Mobile, China Unicom, and China Mobile Broadband. Topsgnaljammer also has a shielding effect on WiFi networks.
Specific frequency bands that block mobile phone signals:
870-880MHzCDMA, CDMA2000
930-960MHzGSM
1805-1850MHzDCS
1850-1920MHz4G(FDD/TDD-LTE)
2010-2025MHzTD-SCDMA
2110-2125MHz4G(FDD-LTE)
2130-2145MHzWCDMA (can be configured according to local frequency band)
2145-2170MHz4G(FDD-LTE)
2300-2390MHz4G(TDD-LTE)
2555-2655MHz4G(TDD-LTE)