Provision of positioning reference signals
Some embodiments advantageously provide methods, wireless devices and network nodes for adapting PRS transmission to hide the local clock information of base stations. According to one aspect, an exemplary process includes a network node for transmitting PRS. The process includes delaying or advancing the transmission of at least one positioning reference signal in accordance with received offset information wherein delaying or advancing the transmission according to the offset information shifts the transmission of the at least one positioning reference signal away from a scheduled transmission time for the at least one positioning reference signal transmission.
1. A method performed by a network node for providing positioning reference signals, PRS, the method comprising:
obtaining offset information relating to the transmission of at least one positioning reference signal;
delaying or advancing the transmission of the at least one positioning reference signal in accordance with the received offset information wherein the delaying or advancing according to the offset information shifts the transmission of the at least one positioning reference signal away from a scheduled transmission time for the at least one positioning reference signal transmission;
the network node is a first network node and the scheduled transmission time for the at least one PRS comprises a first physical resource allocation for the transmission of the at least one PRS in the first network node;
a second network node synchronised with the first network node being scheduled to transmit a corresponding at least one PRS in a corresponding second physical resource allocation; and
the shift away from the scheduled transmission time of the first network node comprising the first network node transmitting the at least one PRS in a third physical resource allocation which is different from said first and second physical resource allocation.
2. The method of claim 1 , wherein the network node is a first network node and the scheduled transmission time of the at least one PRS is transmitted from the first network node and has a corresponding scheduled PRS in a second network node, wherein the corresponding scheduled PRS is intended to be synchronised with the at least one PRS of the first network node.
3. The method of claim 1 , wherein the first, second and third physical resource allocations comprise slots or subframes of a time-frequency resource grid and wherein the first and second resource allocations comprise corresponding slots or subframes of the time-frequency resource grid and the third resource allocation comprises different slots or subframes of the time-frequency resource grid compared to the slots of subframes allocated for the first and second resource allocations or wherein the first, second and third resource allocations comprise PRS occasions and wherein the first and second resource allocations comprise corresponding PRS occasions and the third resource allocation comprises a different PRS occasion to the first and second PRS occasions.
4. The method of claim 1 , wherein the offset information comprises a sequence and wherein the network node applies a first offset value in the sequence when computing the time for transmission of the at least one positioning reference signal and applies a second offset value in the sequence when computing the time for transmission of a subsequent positioning reference signal.
5. The method of claim 1 , further comprising:
sending at least one of:
location information of the network node;
local clock information;
positioning reference signals information.
6. A network node for providing positioning reference signals, PRS, the network node comprising processing circuitry and transceiver circuitry, the network node configured to:
receive, via the transceiver circuitry, offset information relating to the transmission of at least one positioning reference signal; and:
delay or advance the transmission of the at least one positioning reference signal in accordance with the received offset information wherein delay of advance of the transmission according to the offset information shifts the transmission of the first positioning reference signal away from a scheduled transmission time for the at least one positioning reference signal transmission;
the network node being a first network node and the scheduled transmission time for the at least one PRS comprising a first physical resource allocation for the transmission of the at least one PRS in the first network node;
a second network node synchronised with the first network node being scheduled to transmit a corresponding at least one PRS in a corresponding second physical resource allocation; and
the shift away from the scheduled transmission time of the first network node comprising the first network node transmitting the at least one PRS in a third physical resource allocation which is different from the first and second physical resource allocation.
7. The network node of claim 6 , wherein the network node is a first network node and the scheduled transmission time of the at least one PRS is transmitted from the first network node and has a corresponding scheduled PRS in a second network node, wherein the corresponding scheduled PRS is intended to be synchronised with the at least one PRS of the first network node.