Methods and devices for scheduling transmissions in a wireless network based on contention and channel conditions
View Patent ↗Methods and systems for assigning time-division multiplexed (TDM) slots in a multi-channel TDM system are presented. Preferably, a radio access network (RAN) assigns forward link and reverse link transmissions between the RAN and one or more wireless communication devices (WCDs) to TDM slots on various wireless channels. When making these assignments, the RAN may take into account (i) the priority of data that the RAN queues for the WCDs, and (ii) the signal quality at which the WCDs can receive the various wireless channels.
1. A method comprising:
a radio access network (RAN) receiving, from a first wireless communication device (WCD), a first representation of a channel, wherein the channel comprises a set of carrier frequencies, wherein the first representation of the channel is based on a first aggregate signal quality at which the first WCD receives the set of carrier frequencies, and wherein the RAN contains a first data to transmit to the first WCD;
the RAN receiving, from a second WCD, a second representation of the channel, wherein the second representation of the channel is based on a second aggregate signal quality at which the second WCD receives the set of carrier frequencies, and wherein the RAN contains a second data to transmit to the second WCD;
in response to receiving the first and second representations of the channel, the RAN determining (i) that the first WCD and the second WCD are contending with one another for a first time-division multiplexed (TDM) slot on the channel, and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality; and
in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, the RAN transmitting the first data to the first WCD in the first TDM slot.
2. The method of claim 1 , further comprising:
also in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, the RAN transmitting the second data to the second WCD after the RAN transmits the first data to the first WCD.
3. The method of claim 2 , wherein the RAN transmits the second data in a second TDM slot, wherein the first TDM slot and the second TDM slot are both in a given TDM frame of the channel.
4. The method of claim 3 , wherein the RAN uses more bits per symbol to transmit in the first TDM slot than the RAN uses to transmit in the second TDM slot.
5. The method of claim 1 , further comprising:
also in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, the RAN discarding the second data.
6. The method of claim 1 , the method further comprising:
the RAN receiving, from a third WCD, a third representation of the channel, wherein the third representation of the channel is based on a third aggregate signal quality at which the third WCD receives the set of carrier frequencies, and wherein the RAN contains a third data to transmit to the third WCD;
the RAN determining that the third aggregate signal quality is greater than the second aggregate signal quality; and
in response to determining that the third aggregate signal quality is greater than the second aggregate signal quality, the RAN (i) transmitting the third data to the third WCD after the RAN transmits the first data, and (ii) transmitting the second data to the second WCD after the RAN transmits the third data.
7. The method of claim 1 , wherein the carrier frequencies in the set of carrier frequencies are contiguous.
8. The method of claim 1 , wherein the carrier frequencies in the set of carrier frequencies are non-contiguous.
9. The method of claim 1 , wherein determining that the first WCD and the second WCD are contending with one another for the first TDM slot comprises determining that the first data and the second data are both candidates for transmission during the first TDM slot.
10. The method of claim 1 , further comprising:
the RAN determining that both the first data and the second data are associated with a given priority,
wherein transmitting the first data to the first WCD in the first TDM slot also occurs in response to determining that both the first data and the second data are associated with the given priority.
11. An article of manufacture including a non-transitory computer-readable medium, having stored thereon program instructions that, if executed by a radio access network (RAN), cause the RAN to perform operations comprising:
receiving, from a first wireless communication device (WCD), a first representation of a channel, wherein the channel comprises a set of carrier frequencies, wherein the first representation of the channel is based on a first aggregate signal quality at which the first WCD receives the set of carrier frequencies, and wherein the RAN contains a first data to transmit to the first WCD;
receiving, from a second WCD, a second representation of the channel, wherein the second representation of the channel is based on a second aggregate signal quality at which the second WCD receives the set of carrier frequencies, and wherein the RAN contains a second data to transmit to the second WCD;
in response to receiving the first and second representations of the channel, determining (i) that the first WCD and the second WCD are contending with one another for a first time-division multiplexed (TDM) slot on the channel, and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality; and
in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, transmitting the first data to the first WCD in the first TDM slot.
12. The article of manufacture of claim 11 , wherein the program instructions, if executed by the RAN, cause the RAN to perform operations further comprising:
also in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, transmitting the second data to the second WCD after transmitting the first data to the first WCD.
13. The article of manufacture of claim 12 , wherein the RAN transmits the second data in a second TDM slot, wherein the first TDM slot and the second TDM slot are both in a given TDM frame of the channel.
14. The article of manufacture of claim 13 , wherein the RAN uses more bits per symbol to transmit in the first TDM slot than the RAN uses to transmit in the second TDM slot.
15. The article of manufacture of claim 11 , wherein the program instructions, if executed by the RAN, cause the RAN to perform operations further comprising:
also in response to determining (i) that the first WCD and the second WCD are contending with one another for the first TDM slot and (ii) that the first aggregate signal quality is greater than the second aggregate signal quality, discarding the second data.
16. The article of manufacture of claim 11 , wherein the program instructions, if executed by the RAN, cause the RAN to perform operations further comprising:
receiving, from a third WCD, a third representation of the channel, wherein the third representation of the channel is based on a third aggregate signal quality at which the third WCD receives the set of carrier frequencies, and wherein the RAN contains a third data to transmit to the third WCD;
determining that the third aggregate signal quality is greater than the second aggregate signal quality; and
in response to determining that the third aggregate signal quality is greater than the second aggregate signal quality, (i) transmitting the third data to the third WCD after the RAN transmits the first data, and (ii) transmitting the second data to the second WCD after the RAN transmits the third data.
17. The article of manufacture of claim 11 , wherein the carrier frequencies in the set of carrier frequencies are contiguous.
18. The article of manufacture of claim 11 , wherein the carrier frequencies in the set of carrier frequencies are non-contiguous.
19. The article of manufacture of claim 11 , wherein determining that the first WCD and the second WCD are contending with one another for the first TDM slot comprises determining that the first data and the second data are both candidates for transmission during the first TDM slot.
20. The article of manufacture of claim 11 , wherein the program instructions, if executed by the RAN, cause the RAN to perform operations further comprising:
determining that both the first data and the second data are associated with a given priority,
wherein transmitting the first data to the first WCD in the first TDM slot also occurs in response to determining that both the first data and the second data are associated with the given priority.