US Patent 11234104 Time reversal for positioning

In an aspect, a UE estimates channel state(s) of channels(s) between the UE and network node(s) based on DL RS(s) for positioning that are scheduled and transmitted on DL resources from network node(s). The UE may apply TR filter(s) derived based on the estimated channel state(s) to a UL-RS for positioning. The UE may transmit the TR filtered UL-RS on UL resources which are associated with the DL resources of the DL-RS(s) and which are scheduled by the network node(s). The association between the UL resources and the DL resources may be indicated to the UE by the network node(s).