| Mobile Frequency Range | Rx: 869-894; Tx 824-849 |
| Multiple Access Method | FDM |
| Duplex Method | FDD |
| Number of Channels | 832 |
| Channel Spacing | 30kHz |
| Modulation | FM |
AMPS
AMPS (Advanced Mobile Phone Service) was the first cellular mobile system in the United States. AMPS operates as an analog system using 30 kHz wide channels.
NAMPS
AMPS was later enhanced to NAMPS (Narrowband Advanced Mobile Phone Service), a version of AMPS that uses 10 kHz channels and by doing so triples cellular capacity.
AMPS by Any Other Name
Europeans often refer to AMPS as "American Mobile Phone Service." Digital cellular equipment manufacturers and carriers often refer to AMPS as "Analog Mobile Phone Service."
AMPS Standards
AMPS is defined in the EIA/TIA-553 standards. NAMPS is defined in the TIA/EIA/IS-91 standard.
AMPS Network Operators
AT&T Wireless operates a NAMPS network in the United States.
vivian
Cell phone jammers can really be a good item to keep the phones quiet in the public places. Although it is traditionally used in military field, it can be taken into application in many other circumstances I think.