When people buy mobile device, they always concern if the device is 4G LTE compatible, can the device works in different country, for example in Europe and America.
There are very many frequency bands in 4G LTE; different country use different frequency bands, even different operators rolled out different bands in the same country. Find out 4G LTE frequency details
4G LTE offers much faster data transfer than 3G network and brings big challenge for 4G LTE hardware device maker. Manufacturer wants to pack all 4G LTE frequency bands into a device but there is no solution at this moment.
Too many frequency bands are also a headache for us, as cell phone detector factory. Expect the frequency; LTE is defined to support FDD (Frequency Division Duplex) and TDD (Time Division Duplex) frequency band. FDD spectrum requires 2 separate communication channels, one for the uplink and one for the downlink, and TDD requires a single band for transmit and receive are on exactly the same frequency but time separated.
Cellular phone signal detector is to detect the uplink frequency, therefore we need customer to determine the location of detector to prevent mobile phone signal not in the detection range.