![]() Uplink and downlink, also called upload and download, refers to the two-way communication between a cell tower and your phone. What is uplink and downlink in mobile communication? The set of modulation schemes supported for the LTE downlink includes QPSK, 16QAM, and 64QAM, corresponding to two, four, and six bits per modulation symbol respectively. The downlink data modulation transforms the block of scrambled bits to a corresponding block of complex modulation symbols. : to transmit (data) from a spacecraft or satellite to a receiver on earth. Pertaining to radiocommunication service, an uplink (UL or U/L) is the portion of a feeder link used for the transmission of signals from an earth station to a space radio station, space radio system or high altitude platform station. (Satellites do not operate between LEO and MEO because of the inhospitable environment for electronic components in that area, which is caused by the Van Allen radiation belt.) What is the function of the uplink? What is the maximum distance covered by satellite communication? GSM-900 uses 890 – 915 MHz to send information from the Mobile Station to the Base Transceiver Station (BTS) (This is the “uplink”) and 935 – 960 MHz for the other direction (downlink), providing 124 RF channels spaced at 200 kHz. ![]() What is uplink and downlink frequency in GSM? So we can see the B.W of FM is large, as compared to other schemes. whereas in AM B.W is 2 f m, in DSB-SC BW is 2 f m, SSB-SC BW is f m. ![]() In the case of FM, Bandwith is large and noise immunity is high that’s why it is used in satellite communication. Why FM is used in satellite communication? mobile to the base station) as a result of the different requirements between the two directions and the equipment at either end. from base station to mobile) and the uplink (i.e. The actual implementation of the technology will be different between the downlink (i.e. The uplink frequency is higher than that of the down because the transmit amplifier in the down link has a limited power supply power budget as it is on board of the satellite where the satellite is powered by photovoltaic generators. Why the uplink frequency is always greater than the downlink frequency in satellite communication? ![]() The uplink and downlink transmitters use separate frequency bands for transmissions therefore, both downlink and uplink transmitters can transmit at all times and at the same time. Can the same frequency be used for uplink and downlink communication? The downlink frequency is lower than the uplink frequency. … The reason for frequency translation is that the transponder cannot transmit and receive on the same frequency. Why are uplink and downlink frequencies not the same in satellite Mcq?Įxplanation: The transmitter-receiver combination in the satellite is known as a transponder. The downlink frequency is the frequency which is used for transmission of signals from the satellite to the earth station receiver. The uplink frequency is the frequency which is used for transmission of signals from earth station transmitter to the satellite. ![]()
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