When we talk about GSM Rf planning then first thing into mind is Link Budget,here i write about why link Budget analysis in GSM

Link budget analysis provides:

  • Coverage design thresholds
  • EIRP needed to balance the path
  • Maximum allowable path loss
  • It is important that the uplink and downlink paths be balanced, otherwise not enough signal will survive the transmission process to achieve the required signal to noise ratio (SNR) or the bit-error-rate (BER).
  • Path imbalance results from the facts that the gains and losses in the uplink and downlink paths are not the same.
  • The calculations have to be done separately on the uplink and the downlink.

The RF Path

RF Path BTS

INPUTS

  • Base station and Mobile receiver Sensitivity Parameters
  • Minimum acceptable Signal to Noise ratio
  • Environmental / Thermal Noise
  • Receiver Noise figure
  • Antenna gain at the base station and mobile station.
  • Hardware Losses (Cable , Connectors, Combiners, Duplexers etc)
  • Target Coverage reliability.
  • Fade margins.

OUTPUTS

  • Base station ERP
  • Maximum allowable path loss
  • Cell size estimates
  • Cell count estimates