Definition and Specifications of Public Transceiver
Public transceiver is a wireless walkie talkie which works at an assigned frequency. Its output power shouldn't be more than 0.5W. Its specifications are as followed.
1. Operating Frequency (Channel: 409, Unit: MHz): 409.7500, 409.7625, 409.7750, 409.7875, 409.8000, 409.8125, 409.8250, 409.8375, 409.850,4 09.8625, 409.8750, 409.8875, 4099125, 409.9250, 409.9375, 409.9500, 409.9625, 409.9750, 409.9875.
2. Modulation Mode: F3E.
3. Equivalent Isotropic Radiated Power (EIRP): < 0.5W.
4. Transmission Frequency Stability: <+5ppm.
5. Transceiver Spurious Radiation: <50uW.
6. Receiver Spurious Radiation: <20nW.
7. Channel Spacing: 12.50 kHz.
Reasons for Frequency Limitation
Frequency division has been conducted by national radio station management committee to make calls of most users free from interference and make rational use of frequency resources. Different frequency ranges are applied in different industries. Users need to apply for frequency points when they buy transceivers.
Differences Between Analog Transceiver and Digital Transceiver
Analog transceiver is a communication device which modulates voice signals and signaling with continuous waves on the carrier of the walkie talkie and then optimizes these signals by amplification or other methods.
Digital transceiver digitalizes voice signals by a specific way of digital encoding and a certain form of baseband modulation. Then these signals are optimized by digital signal processors. Compared with traditional analog interphone, the digital type achieves greater anti-interference performance, higher security, a narrower bandwidth channels occupy, and more efficient transmission of information. The fact should be pointed out that trunking walkie talkie is not belong to digital interphone even it only adopt digital signals.
Applications of Digital Transceiver
Digital transceiver brings about higher audio quality and better confidentiality. It achieves perfect performance for dispatching and great ability of data transmission. Customers with a long-term plan and sufficient budget funds can consider to use the digital walkie talkie.