TD LTE secondary component carrier in unlicensed bands
View Patent ↗A method is provided for communication in a wireless telecommunication system. The method comprises adaptively designating, by a network element following a frame-based communication protocol, for use as a secondary component carrier in a carrier aggregation scheme, at least a portion of radio resources on an unlicensed band.
1. A method for communication in a wireless telecommunication system, the method comprising:
adaptively designating, by a network element following a frame-based communication protocol, to utilize as a secondary component carrier in a carrier aggregation scheme, at least a portion of radio resources on an unlicensed band, wherein the radio resources that are adaptively designated facilitate wireless communication, wherein the portion of the radio resources is not being utilized by another network element following a contention-based communication protocol; and
determining, by the network element following the frame-based communication protocol, a subframe in which the network element following the contention-based communication protocol is scheduled to transmit a beacon signal, the determination being based on information requested from and received from a user equipment (UE) in communication with the network element following the contention-based communication protocol,
wherein, when the network element following the frame-based communication protocol is scheduled to transmit a downlink subframe concurrently with the subframe in which the network element following the contention-based communication protocol is scheduled to transmit the beacon signal, the network element following the frame-based communication protocol instead transmits a coexistence subframe, wherein no transmission occurs in a portion of the coexistence subframe during which the beacon signal is scheduled to be transmitted, and wherein, during the remainder of the coexistence subframe, a coexistence subframe-based blocking signal is transmitted to prevent a contention-based protocol transmission during a subframe immediately following the beacon signal subframe.
2. The method of claim 1 , wherein the portion of the radio resources is utilized by the network element following the frame-based communication protocol only for downlink transmission to the UE.
3. The method of claim 2 , wherein the frame-based communication protocol is a long-term evolution (LTE) protocol based on a Third Generation Partnership Project (3 GPP) standard, and wherein the contention-based communication protocol is a Wi-Fi protocol based on an IEEE 802.11 standard.
4. The method of claim 2 , wherein the secondary component carrier carries user data and a primary component carrier carries medium access control (MAC) signaling and user data, wherein the primary component carrier is configured for downlink and uplink transmissions to and from the UE using radio resources on a licensed band.
5. The method of claim 2 , wherein the network element following the frame-based communication protocol is a home eNodeB (HeNB) configured to utilize a primary carrier component on a licensed band to receive an uplink acknowledgement/negative acknowledgement (ACK/NACK) message from the UE in response to transmitting downlink data to the UE using the portion of radio resources on the unlicensed band of the secondary component carrier, and wherein the network element following the contention-based communication protocol is a Wi-Fi access point (AP) scheduled to transmit the beacon signal to provide timing synchronization to UEs in communication with the network element following the contention-based protocol.
6. The method of claim 1 , wherein the information requested from the UE includes at least one of:
beacon timing;
a maximum time variation of the beacon;
path loss;
a parameter indicating a duration of the beacon transmission;
a system load on a system that includes the network element following the contention-based communication protocol; and
a maximum size of a MAC payload on the network element following the contention-based communication protocol.
7. The method of claim 1 , wherein the network element following the frame-based communication protocol transmits a blocking subframe in a subframe that occurs at a position within a frame-based protocol radio frame that corresponds to a position within a previous frame-based protocol radio frame where a coexistence subframe was transmitted but that is not concurrent with a subframe in which the network element following the contention-based communication protocol is scheduled to transmit a beacon signal, wherein the blocking subframe contains a blocking subframe-based blocking signal in an initial portion of the blocking subframe and contains data in the remainder of the blocking subframe.
8. The method of claim 1 , wherein the network element following the frame-based communication protocol transmits a special subframe-based blocking signal in a guard period in a special subframe S, as defined in a Third Generation Partnership Project (3GPP) standard, the special subframe-based blocking signal preventing uplink contention-based protocol transmissions during an uplink pilot time slot in the special subframe S.
9. The method of claim 1 , wherein, when the network element following the frame-based communication protocol is scheduled to transmit a special subframe S, as defined in a 3GPP standard, concurrently with the subframe in which the network element following the contention-based communication protocol is scheduled to transmit the beacon signal, the network element following the frame-based communication protocol does not schedule a transmission on a portion of S concurrent with the beacon signal.
10. The method of claim 9 , wherein, when the portion of S is a downlink pilot time slot (DwPTS), no transmission occurs on a downlink during the DwPTS, and a primary synchronization signal and a broadcast channel are not transmitted on an unlicensed secondary carrier.
11. The method of claim 9 , wherein, when the portion of S is an uplink pilot time slot (UpPTS), a system information block is sent such that a UE does not transmit a synchronization reference signal or a random access channel during the UpPTS.
12. The method of claim 1 , wherein the network element following the frame-based communication protocol sends a channel claim request to request utilize of the unlicensed secondary component carrier, and when the network element following the frame-based communication protocol receives a positive response to the request, the network element following the frame-based communication protocol utilizes the unlicensed secondary component carrier and sends a channel claim acknowledgement, and when the network element following the frame-based communication protocol does not receive a positive response to the request, the network element following the frame-based communication protocol sends a channel non-claim acknowledgement, utilizes an unlicensed secondary component carrier with a lower ranking, and sends another channel claim request.
13. The method of claim 1 , wherein the network element following the frame-based communication protocol monitors a plurality of component carriers to compare an actual quality of service (QoS) to an expected QoS for the component carriers, and when the network element following the frame-based communication protocol determines that an additional amount of bandwidth will improve a QoS, the network element following the frame-based communication protocol utilizes the portion of the bandwidth on the unlicensed secondary component carrier.
14. The method of claim 13 , wherein, when the network element following the frame-based communication protocol finds a plurality of unlicensed secondary component carriers that are capable of providing the portion of the bandwidth and that have active transmissions that follow the contention-based communication protocol, the network element following the frame-based communication protocol ranks the plurality of unlicensed secondary component carriers and selects the unlicensed secondary component carrier with the highest ranking, wherein the ranking takes into account at least one of a system load on a contention-based system, an expected frame-based spectral efficiency, an amount of control over bandwidth sharing that is possible under allowed uplink and downlink configurations, and a number of attached UEs that are capable of operating in the selected unlicensed secondary component carrier.
15. The method of claim 13 , wherein, when the network element following the frame-based communication protocol finds a plurality of unlicensed secondary component carriers that are capable of providing the portion of the bandwidth and that do not have active transmissions that follow a contention-based protocol, the network element following the frame-based communication protocol selects a component carrier over which most of the attached UEs are capable of operating.
16. A network element following a frame-based communication protocol, the network element comprising:
a processor configured such that the network element following the frame-based communication protocol adaptively designates, for utilize as a secondary component carrier in a carrier aggregation scheme, at least a portion of radio resources on an unlicensed band, wherein the radio resources that are adaptively designated facilitate wireless communication,
wherein the portion of the radio resources is not being utilized by another network element following a contention-based communication protocol, and
wherein the network element following the frame-based communication protocol determines a subframe in which the network element following the contention-based communication protocol is scheduled to transmit a beacon signal, the determination being based on information requested from and received from a user equipment (UE) in communication with the network element following the contention-based communication protocol,
wherein, when the network element following the frame-based communication protocol is scheduled to transmit a downlink subframe concurrently with the subframe in which the network element following the contention-based communication protocol is scheduled to transmit the beacon signal, the network element following the frame-based communication protocol instead transmits a coexistence subframe, wherein no transmission occurs in a portion of the coexistence subframe during which the beacon signal is scheduled to be transmitted, and wherein, during the remainder of the coexistence subframe, a coexistence subframe-based blocking signal is transmitted to prevent a contention-based protocol transmission during a subframe immediately following the beacon signal subframe.
17. The network element following the frame-based communication protocol of claim 16 , wherein the portion of the radio resources is utilized by network element following the frame-based communication protocol only for downlink transmission to the UE.
18. The network element following the frame-based communication protocol of claim 17 , wherein the frame-based protocol is a long-term evolution (LTE) protocol based on a Third Generation Partnership Project (3GPP) standard, and wherein the contention-based communication protocol is a Wi-Fi protocol based on an IEEE 802.11standard.
19. The network element following the frame-based communication protocol of claim 17 , wherein the secondary component carrier carries user data and a primary component carrier carries medium access control (MAC) signaling and user data, wherein the primary component carrier is configured for downlink and uplink transmissions to and from the UE using radio resources on a licensed band.
20. The network element following the frame-based communication protocol of claim 17 , wherein the network element following the frame-based communication protocol is a home eNodeB (HeNB) configured to utilize a primary carrier component on a licensed band to receive an uplink acknowledgement/negative acknowledgement (ACK/NACK) from the UE in response to transmitting downlink data to the UE using the portion of radio resources on the unlicensed band, and wherein the network element following the contention-based communication protocol is a WiFi access point (AP) scheduled to transmit the beacon signal to provide timing synchronization to UEs in communication with the network element following the contention-based communication protocol.
21. A user equipment (UE) comprising:
a processor configured such that the UE receives at least a portion of radio resources on an unlicensed band, the at least a portion of radio resources on the unlicensed band having been adaptively designated by a network element following a frame-based communication protocol to utilize as a secondary component carrier in a carrier aggregation scheme, wherein the radio resources that are adaptively designated facilitate wireless communication,
wherein the portion of the radio resources is not being utilized by another network element in communication with the UE, the other network element following a contention-based communication protocol,
wherein the network element following the frame-based communication protocol is configured to determine a subframe in which the other network element following the contention-based communication protocol is scheduled to transmit a beacon signal, the determination being based on information requested from and received from the UE, and
wherein, when the network element following the frame-based communication protocol is scheduled to transmit a downlink subframe concurrently with the subframe in which the network element following the contention-based communication protocol is scheduled to transmit the beacon signal, the network element following the frame-based communication protocol instead transmits a coexistence subframe, wherein no transmission occurs in a portion of the coexistence subframe during which the beacon signal is scheduled to be transmitted, and wherein, during the remainder of the coexistence subframe, a coexistence subframe-based blocking signal is transmitted to prevent a contention-based protocol transmission during a subframe immediately following the beacon signal subframe.
22. The UE of claim 21 , wherein the portion of the radio resources is utilized by the network element following the frame-based communication protocol only for downlink transmission to the UE, and wherein radio resources on a licensed band of a primary component carrier are utilized for downlink and uplink transmissions between the UE and the network element following the frame-based communication protocol.
23. The UE of claim 22 , wherein the frame-based communication protocol is a long-term evolution (LTE) protocol based on a Third Generation Partnership Project (3GPP) standard, and wherein the contention-based communication protocol is a WiFi protocol based on an IEEE 802.11 standard.
24. The UE of claim 22 , wherein the UE is configured to transmit uplink control information using radio resources on the licensed band in response to receiving downlink data from the network element following the frame-based communication protocol using the portion of radio resources on the unlicensed band, and wherein the network element following the contention-based communication protocol is a Wi-Fi access point (AP) scheduled to transmit the beacon signal to provide timing synchronization to UEs attached to the network element following the contention-based communication protocol.
25. The UE of claim 21 , wherein the secondary component carrier carries user data and a primary component carrier on a licensed band carries medium access control (MAC) signaling and user data, wherein the secondary component carrier is only configured to carry downlink data transmitted from the network element following the frame-based communication protocol to the UE, wherein the primary component carrier is configured to carry downlink and uplink control information between the UE and the network element following the frame-based communication protocol.
26. A method for communication in a wireless telecommunication system, the method comprising:
adaptively using, by a network element following a frame-based communication protocol, at least a portion of radio resources not being utilized by another network element following a contention-based communication protocol, wherein the radio resources that are adaptivel utilized facilitate wireless communication, wherein the portion of the radio resources is on an unlicensed band that is utilized as a secondary component carrier in a carrier aggregation scheme; and
determining, by the network element following the frame-based communication protocol, a subframe in which the other network element following the contention-based communication protocol is scheduled to transmit a beacon signal, the determination being based on information requested from and received from a user equipment (UE) in communication with the network element following the contention-based communication protocol,
wherein, when the network element following the frame-based communication protocol is scheduled to transmit a downlink subframe concurrently with the subframe in which the network element following the contention-based communication protocol is scheduled to transmit the beacon signal, the network element following the frame-based communication protocol instead transmits a coexistence subframe, wherein no transmission occurs in a portion of the coexistence subframe during which the beacon signal is scheduled to be transmitted, and wherein, during the remainder of the coexistence subframe, a coexistence subframe-based blocking signal is transmitted to prevent a contention-based protocol transmission during a subframe immediately following the beacon signal subframe.
27. The method of claim 26 , wherein the frame-based communication protocol is a long-term evolution (LTE) protocol based on a Third Generation Partnership Project (3GPP) standard, and wherein the contention-based communication protocol is a WiFi protocol based on an IEEE 802.11 standard.
28. The method of claim 26 , wherein the network element following the contention-based communication protocol is not aware of the utilize of the radio resources by the network element following the frame-based communication protocol.
29. The method of claim 28 , wherein radio resources are opportunistically borrowed from the network element following the contention-based protocol without affecting the existing operation of the network element following the contention-based communication protocol and wherein radio resource usage is changed adaptively based on a requirement of resources of the network element following the frame-based communication protocol.
30. The method of claim 26 , wherein the portion of the radio resources on the unlicensed band that is utilized as the secondary component carrier is only utilized for downlink transmissions from the network element following the frame-based communication protocol to the UE, wherein radio resources on a licensed band of a primary component carrier are utilized for downlink and uplink transmissions between the UE and the network element following the frame-based communication protocol.
31. The method of claim 26 , wherein the network element following the frame-based communication protocol blocks a channel such that a device following the contention-based communication protocol senses a busy medium while the network element following the frame-based communication protocol is using the channel.
32. The method of claim 26 , wherein the network element following the frame-based communication protocol determines to utilize the portion of the radio resources when the network element following the frame-based communication protocol determines that a quality of service in a frame-based transmission can be improved by using the portion of the bandwidth.
33. The method of claim 26 , wherein the network element following the frame-based communication protocol determines the portion of the radio resources based on knowledge of the radio resource usage by the network element following the contention-based communication protocol.
34. A method for communication in a wireless telecommunication system, the method comprising:
adaptively using, by a first network element following a Third Generation Partnership Project (3GPP) long-term evolution (LTE) protocol, at least a portion of radio resources that are not being utilized by a second network element following a WiFi protocol based on an IEEE 802.11 standard, wherein the portion of radio resources is on an unlicensed band that is utilized as a secondary component carrier to supplement a primary component carrier operating on a licensed band in a carrier aggregation scheme, and wherein the radio resources that are adaptively utilized facilitate wireless communication;
transmitting, from the first network element, downlink traffic to a user equipment (UE) using radio resources on the primary component carrier;
offloading, by the first network element, some of the downlink traffic from the primary component carrier such that the offloaded downlink traffic is transmitted to the UE using the portion of radio resources on the secondary component carrier; and
receiving, by the first network element, uplink traffic from the UE on the primary component carrier in response to transmitting the offloaded downlink traffic on the secondary component carrier,
wherein, when the first network element is scheduled to transmit a downlink subframe concurrently with the subframe in which the second network element is scheduled to transmit the beacon signal, the first network element instead transmits a coexistence subframe, wherein no transmission occurs in a portion of the coexistence subframe during which the beacon signal is scheduled to be transmitted, and wherein, during the remainder of the coexistence subframe, a coexistence subframe-based blocking signal is transmitted to prevent a contention-based protocol transmission during a subframe immediately following the beacon signal subframe.
35. The method of claim 34 , wherein the primary component carrier is configured for downlink and uplink transmissions between the first network element and the UE, while the secondary component carrier is only configured for downlink transmission from the first network element to the UE.