METHOD AND SYSTEM FOR CO-EXISTENCE OF C-V2X TRANSMISSIONS WITH OTHER TECHNOLOGIES
Method and device for co-existence of cellular vehicle-to-everything (C-V2X) transmissions with other technologies, the method comprising: in a self-vehicle, in each C-V2X slot, measuring C-V2X energy and non-C-V2X energy of all subchannels, measuring pre-slot energy of all subchannels, if pre-slot energy exists in particular subchannels, using the measured pre-slot energy to overwrite stored historical measured energies of prior cycles in the particular subchannels, thereby obtaining an overwritten energy value, and if pre-slot energy is not measured in a particular subchannel scheduled for an upcoming transmission, perform the upcoming transmission as scheduled in the particular subchannel.
1 . A method for co-existence of cellular vehicle-to-everything (C-V2X) transmissions with other technologies, comprising: in a self-vehicle, in each C-V2X slot:
measuring C-V2X energy and non-C-V2X energy of all subchannels;
measuring pre-slot energy of all subchannels, and, if pre-slot energy exists in particular subchannels, using the measured pre-slot energy to overwrite stored historical measured energies of prior cycles in the particular subchannels, thereby obtaining an overwritten energy value; and
if pre-slot energy is not measured in a particular subchannel scheduled for an upcoming transmission, perform the upcoming transmission as scheduled in the particular subchannel.
2 . The method of claim 1 , further comprising, if pre-slot energy is measured in a subchannel scheduled for an upcoming transmission, cancelling transmission in all suchannels selected for transmission.
3 . The method of claim 2 , further comprising forcing resource reselection.
4 . The method of claim 1 , further comprising, if pre-slot energy is measured in a subchannel not scheduled for an upcoming transmission, transmit as scheduled.
5 . The method of claim 1 , wherein the non-C-V2X energy is Dedicated Short-Range Communications (DSRC) energy.
6 . The method of claim 1 , wherein the overwriting of the stored historical measured energies of prior cycles in the particular subchannels is in the form Energy (cycle-9:cycle, current slot-1:current slot)=pre-slot energy.
7 . The method of claim 3 , wherein the forcing resource reselection includes reselecting resources using the overwritten energy value.
8 . A cellular vehicle-to-everything (C-V2X) access layer device, comprising:
an enhanced energy measurement unit configured to measure pre-slot energy in all subchannels before each slot starts and for outputting measured pre-slot energy, to use the measured pre-slot energy to overwrite slot subchannel energy measurements from the last 1 second to obtain an overwritten energy value and to force the measured pre-slot energy for the relevant slots and subchannels during current and past cycles;
a pre-slot activation unit configured to control a timing of the pre-slot energy measurement;
an enhanced resource energy measurement unit configured to measure in-slot non-C-V2X energy in addition to C-V2X energy; and
a legacy resource reservation module configured to determine the transmission slot using the measured pre-slot energy values, in-slot energy measurements values and the overwritten energy value.
9 . The C-V2X access layer device of claim 8 , wherein the legacy resource reservation module is configured to force resource reselection.
10 . The C-V2X access layer device of claim 9 , wherein resource reselection includes resource reselection using the overwritten energy value.
11 . The C-V2X access layer device of claim 8 , wherein the overwritten energy value is given by Energy (cycle-9:cycle, current slot-1:current slot)=pre-slot energy.
12 . The C-V2X access layer device of claim 8 , wherein the non-C-V2X energy is Dedicated Short-Range Communications (DSRC) energy.
13 . The C-V2X access layer device of claim 8 , included in a vehicle.