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Capability of the TETRA Equalizer on Multi-path Interference

I'm designing an indoor TETRA coverage making use of a Bi-Directional Amplifer (BDA). Due to the client's requirements, the designed coverage for the outdoor carpark is having both direct line-of-sight (LOS) from donor celllsite and its repeated signal from BDA. LOS and repeated signals are similar in strength. The BDA unit has a round-trip system delay of 15us while feeder propagation time is negligible. So, the time difference between LOS and repeated signal can assume 15us. This scenario can be regarded as multi-path interference.

Knowing that the User Equipment (UE) deploys the equalizers to handle the multi-path effect, I'm unable to find the equalizer capability requirement in the GSM Specification. For a common 2G UE of TERA or GSM, what's the minimum time spread on multi-path signals that the equalizer is able to handle?

Parents
  • Tetra is different and has a maximum difference between direct and indirect paths of 14 Usec.   Getting enhancers to work means you have to in effect ensure that there is no direct path and only enhanced paths are available. (Tunnels are great for this).  However any car park work or other outdoor areas will struggle.  (Why do you want enhanced coverage outdoors if the direct path is ok already?    

Reply
  • Tetra is different and has a maximum difference between direct and indirect paths of 14 Usec.   Getting enhancers to work means you have to in effect ensure that there is no direct path and only enhanced paths are available. (Tunnels are great for this).  However any car park work or other outdoor areas will struggle.  (Why do you want enhanced coverage outdoors if the direct path is ok already?    

Children
No Data