System and method for joint transmission over licensed and unlicensed bands using fountain codes

1. A method for wireless transmission, the method comprising:

encoding a traffic flow using a rate-less code to obtain rate-less-encoded packets; and

simultaneously transmitting, by a transmit point, a first subset of the rate-less-encoded packets to a receive point over a licensed band of a unified air interface operating in accordance with a common cellular radio access technology (RAT), and a second subset of the rate-less-encoded packets to the receive point over an unlicensed band of the unified air interface operating in accordance with the common cellular RAT, the unified air interface providing a common physical and medium access control (MAC) connection between the receive point and the transmit point; and

wherein the method further comprises:

dynamically adjusting a rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band from a first transmission rate to a second transmission rate in accordance with a quality of service (QoS) metric of the unlicensed band.

2. The method of claim 1 , wherein

both the first transmission rate and the second transmission rate are non-zero transmission rates, and the first subset of the rate-less-encoded packets and the second subset of the rate-less-encoded packets are transmitted at different rates.

3. The method of claim 1 , wherein dynamically adjusting the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band from the first transmission rate to the second transmission rate in accordance with the QoS metric of the unlicensed band comprises:

increasing the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band, and decreasing a rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band, when a packet loss rate on the unlicensed band exceeds a threshold, an increase in the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band at least partially compensating for a decrease in the rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band.

4. The method of claim 1 , wherein dynamically adjusting the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band from the first transmission rate to the second transmission rate in accordance with the QoS metric of the unlicensed band comprises:

decreasing the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band, and increasing a rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band, when a packet loss rate on the unlicensed band falls below a threshold, an increase in the rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band at least partially compensating for a decrease in the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band.

5. The method of claim 4 , wherein increase in the rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band is proportional to decrease in the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band.

6. The method of claim 1 , wherein dynamically adjusting the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band from the first transmission rate to the second transmission rate in accordance with the QoS metric of the unlicensed band comprises:

increasing the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band, and decreasing a rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band, when a contention level or latency of the unlicensed band exceeds an upper threshold; and

decreasing the rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band, and increasing the rate in which the second subset of the rate-less-encoded packets are transmitted over the unlicensed band, when the contention level or latency of the unlicensed band falls below a lower threshold.

7. The method of claim 1 , further comprising:

dynamically adjusting rates in which the rate-less-encoded packets are communicated over at least one of the licensed band and the unlicensed band in accordance with a characteristic of the traffic flow.

8. The method of claim 7 , wherein dynamically adjusting the rates in which the rate-less-encoded packets are transmitted over at least one of the licensed band and the unlicensed band in accordance with the characteristic of the traffic flow comprises:

determining rates for the licensed band and the unlicensed band in accordance with a QoS or a priority level of the traffic flow; and

transmitting the first subset of the rate-less-encoded packets over the licensed band and the second subset of the rate-less-encoded packets over the unlicensed band in accordance with the determined rates.

9. The method of claim 1 , wherein the rate-less code is applied at a physical layer.

10. The method of claim 1 , wherein encoding the traffic flow using the rate-less code to obtain the rate-less-encoded packets comprises applying the rate-less code at a MAC layer.

11. The method of claim 1 , wherein encoding the traffic flow using the rate-less code to obtain the rate-less-encoded packets comprises applying the rate-less code at a radio link control (RLC) layer.

12. The method of claim 1 , encoding the traffic flow using the rate-less code to obtain the rate-less-encoded packets comprises applying the rate-less code at an application layer.

13. The method of claim 1 , wherein automatic repeat request (ARQ) signaling is excluded from a radio link control (RLC) layer and a media access control (MAC) layer.

14. The method of claim 1 , wherein transmitting the first subset of the rate-less-encoded packets over the licensed band and the second subset of the rate-less-encoded packets over the unlicensed band comprises:

transmitting the first subset of the rate-less-encoded packets and the second subset of the rate-less-encoded packets directly to the receive point in accordance with a common telecommunication protocol.

15. The method of claim 2 , wherein the QoS metric of the unlicensed band includes a packet loss rate, contention level, or latency of the unlicensed band.

16. The method of claim 1 , wherein the first subset of the rate-less-encoded packets is transmitted at a rate that is based on a quality of service (QoS) of the unlicensed band.

17. A wireless multi-band transmitter comprising:

a processor; and

a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:

encode a traffic flow using a rate-less code to obtain rate-less-encoded packets; and

transmit a first subset of the rate-less-encoded packets to a receive point over a licensed band of a unified air interface operating in accordance with a common cellular radio access technology (RAT), and a second subset of the rate-less-encoded packets to the receive point over an unlicensed band of the unified air interface operating in accordance with the common cellular RAT, the unified air interface providing a common physical and medium access control (MAC) connection between the receive point and the wireless multi-band transmitter; and

wherein the programming further includes instructions to:

dynamically adjust a rate in which the first subset of the rate-less-encoded packets are transmitted over the licensed band from a first transmission rate to a second transmission rate in accordance with a quality of service (QoS) metric of the unlicensed band.

18. The wireless multi-band transmitter of claim 17 , wherein

both the first transmission rate and the second transmission rate are non-zero transmission rates, and the first subset of the rate-less-encoded packets and the second subset of the rate-less-encoded packets are transmitted at different rates.

19. The wireless multi-band transmitter of claim 18 , wherein the QoS metric of the unlicensed band includes a packet loss rate, contention level, or latency of the unlicensed band.

20. A method for receiving wireless transmissions, the method comprising:

receiving, by a receive point, a wireless transmission from a single transmit point carrying a first subset of rate-less-encoded packets of a single traffic flow over a licensed band of a unified air interface operating in accordance with a common cellular radio access technology (RAT), and a second subset of rate-less-encoded packets of the single traffic flow over an unlicensed band of the unified air interface operating in accordance with the common cellular RAT, the unified air interface providing a common physical and medium access control (MAC) connection between the receive point and the single transmit point; and

jointly decoding both the first subset of rate-less-encoded packets received over the licensed band and the second subset of rate-less-encoded packets received over the unlicensed band in accordance with a same rate-less code to obtain the single traffic flow, the first subset of rate-less-encoded packets and the second subset of rate-less-encoded packets having been generated from the single traffic flow using the same rate-less code by the single transmit point, wherein a common physical or MAC layer processing entity of the receive point jointly decodes the first subset of rate-less-encoded packets received over the licensed band and the second subset of rate-less-encoded packets received over the unlicensed band in accordance with the same rate-less code; and

wherein the first subset of rate-less-encoded packets is received at a rate that is dynamically adjustable based on a quality of service (QoS) of the unlicensed band.

21. The method of claim 20 , wherein the first subset of the rate-less-encoded packets is and the second subset of rate-less-encoded packets are received at different rates.

22. A wireless multi-band receiver comprising:

a processor; and

a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:

receive a wireless transmission carrying a first subset of rate-less-encoded packets of a single traffic flow over a licensed band of a unified air interface operating in accordance with a common cellular radio access technology (RAT), and a second subset of rate-less-encoded packets of the single traffic flow over a unlicensed band of the unified air interface operating in accordance with the common cellular RAT, the unified air interface providing a common physical and medium access control (MAC) connection between the wireless multi-band receiver and a single transmit point; and

jointly decode both the first subset of rate-less-encoded packets received over the licensed band and the second subset of rate-less-encoded packets received over the unlicensed band in accordance with a same rate-less code to obtain the single traffic flow, the first subset of rate-less-encoded packets and the second subset of rate-less-encoded packets having been generated from the single traffic flow using the same rate-less code by the single transmit point, wherein a common physical or MAC layer processing entity of the wireless multi-band receiver jointly decodes the first subset of rate-less-encoded packets received over the licensed band and the second subset of rate-less-encoded packets received over the unlicensed band in accordance with the same rate-less code; and

wherein the first subset of rate-less-encoded packets is received at a rate that is dynamically adjustable based on a quality of service (QoS) metric of the unlicensed band.