A patch cable, or patch lead, is a short and flexible coaxial cable designed to connect a larger feeder cable to a user device.
In the case of 4G mobile broadband, traditionally modems have used either a TS-9 or CRC9 connector. These are simple, push-on RF interfaces which provide good performance up to about 3 GHz, making them suitable for 3G and 4G frequencies. When used with a high performance coaxial cable like LMR-100 the connectors provide modest performance over the 3.5 GHz 5G frequency band.
Industrial 4G modems use the more robust SMA connector as the larger thread-on / screw-on interfacing provides far more mechanical durability.
Patch cables are of course not limited to cellular connectivity. Many other technologies such as WiFi and point to point wireless use short patch cables to interconnect active and passive components. Micro-cable patch leads are also available for connecting RF modules with U.FL and MHF4 interfaces.