Relays in wireless communication networks
Methods and apparatus for transmitting packets in wireless communication networks are disclosed. The methods include a relay mobile station measuring channel quality between the relay mobile station and a destination mobile station in response to a request for relay mobile stations from a base station The relay mobile station reports a channel quality indicator to the base station if the channel quality for a link between the base station and the destination mobile station via the relay mobile station is greater than a predetermined channel quality. The base station determines the relay mobile station that provides an optimal route for transmitting the packets from the base station to the destination mobile station.
1. A method, comprising:
transmitting packets in a wireless communication network comprising;
at least one relay mobile station measuring channel quality between the relay mobile station and a destination mobile station in response to a request for at least one relay mobile station from a base station, each relay mobile station operating as a mobile station in the wireless communication network;
the relay mobile station reporting a channel quality indicator to the base station if a channel quality for a link between the base station and the destination mobile station via the relay mobile station is greater than a predetermined channel quality; and
the base station determining the relay mobile station that provides an optimal route for transmitting the packets from the base station to the destination mobile station based on the following equation:
1
CC
(
BS
→
D
)
-
1
CC
(
BS
→
R
)
+
CC
(
BS
→
D
)
-
1
CC
(
R
→
D
)
>
threshold
in which the threshold is predetermined to compensate for the overhead of the relay mobile station, CC(BS→D) refers to the theoretical channel capacity for a communication link between the base station and the destination mobile station, CC(BS→R) refers to the theoretical channel capacity for a communication link between the base station and the relay mobile station, CC(R→D) refers to the theoretical channel capacity for a communication link between the relay mobile station and the destination mobile station.
2. The method of claim 1 , further comprising the base station broadcasting identifiers of the destination mobile stations for which a relay mobile station is required.
3. The method of claim 1 , further comprising broadcasting a channel quality indicator for a direct link between the base station and each destination mobile station for which a relay mobile station is required.
4. The method of claim 1 , wherein the predetermined channel quality is the channel quality for a direct link between the base station and the destination mobile station.
5. The method of claim 1 , further comprising the destination mobile station or the relay mobile station transmitting an interference indicator to the base station where the relay mobile station shares an uplink slot with an uplink transmission from another mobile station.
6. The method of claim 1 , wherein the relay mobile station shares an uplink slot with an uplink transmission from another mobile station.
7. The method of claim 5 , further comprising the base station scheduling transmissions to the destination mobile station via a relay mobile station to minimize interference with uplink transmissions from another mobile station.
8. The method of claim 1 , further comprising the destination mobile station reporting a channel quality indicator to the base station if the channel quality for a link between an uplink mobile station and the destination mobile station is above a predetermined threshold.
9. A relay mobile station for transmitting packets in a wireless communication network including:
measuring channel quality between the relay mobile station and a destination mobile station in response to a request for at least one relay mobile station from a base station, the relay mobile station operating as a mobile station in the wireless communication network, and the base station determining the relay mobile station that provides an optimal route for transmitting the packets from the base station to the destination mobile station based on the following equation:
1
CC
(
BS
→
D
)
-
1
CC
(
BS
→
R
)
+
CC
(
BS
→
D
)
-
1
CC
(
R
→
D
)
>
threshold
in which the threshold is predetermined to compensate for the overhead of the relay mobile station, CC(BS→D) refers to the theoretical channel capacity for a communication link between the base station and the destination mobile station, CC(BS→R) refers to the theoretical channel capacity for a communication link between the base station and the relay mobile station, CC(R→D) refers to the theoretical channel capacity for a communication link between the relay mobile station and the destination mobile station; and
reporting a channel quality indicator to the base station if the channel quality for a link between the base station and the destination mobile station via the relay mobile station is greater than a predetermined channel quality.
10. The relay mobile station of claim 9 , further comprising the destination mobile station or the relay mobile station transmitting an interference indicator to the base station in response to a request from the base station where the relay mobile station shares an uplink slot with an uplink transmission from another mobile station.
11. An article comprising: a non-transitory computer-readable medium having stored thereon instructions that, if executed, result in at least the following:
transmitting packets in a wireless communication network between a base station and a destination mobile station;
measuring at least one relay mobile station channel quality between the relay mobile station and the destination mobile station in response to a request for at least one relay mobile station from the base station, each relay mobile station operating as a mobile station in the wireless communication network;
reporting by the relay mobile station a channel quality indicator to the base station if a channel quality for a link between the base station and the destination mobile station via the relay mobile station is greater than a predetermined channel quality; and
determining at the base station the relay mobile station that provides an optimal route for transmitting the packets from the base station to the destination mobile station based on the following equation:
1
CC
(
BS
→
D
)
-
1
CC
(
BS
→
R
)
+
CC
(
BS
→
D
)
-
1
CC
(
R
→
D
)
>
threshold
in which the threshold is predetermined to compensate for the overhead of the relay mobile station, CC(BS→D) refers to the theoretical channel capacity for a communication link between the base station and the destination mobile station, CC(BS→R) refers to the theoretical channel capacity for a communication link between the base station and the relay mobile station, CC(R→D) refers to the theoretical channel capacity for a communication link between the relay mobile station and the destination mobile station.
12. The article of claim 11 , further comprising broadcasting by the base station identifiers of the destination mobile stations for which a relay mobile station is required.
13. The article of claim 11 , further comprising broadcasting a channel quality indicator for a direct link between the base station and each destination mobile station for which a relay mobile station is required.
14. The article of claim 11 , further comprising causing the predetermined channel quality to be the channel quality for a direct link between the base station and the destination mobile station.
15. The article of claim 11 , further comprising transmitting by the mobile station or the relay mobile station an interference indicator to the base station where the relay mobile station shares an uplink slot with an uplink transmission from another mobile station.
16. The article of claim 11 , wherein the relay mobile station that provides an optimal route.
17. The article of claim 16 , further comprising scheduling by the base station transmissions to the destination mobile station via a relay mobile station to minimize interference with uplink transmissions from another mobile station.
18. The article of claim 11 , further comprising reporting by the mobile station a channel quality indicator to the base station if the channel quality for a link between an uplink mobile station and the destination mobile station is above a predetermined threshold.