Multi-carrier power pooling
View Patent ↗Novel techniques for pooling the available transmit power of a beam across the subcarriers that are or that are scheduled to be in use (and not across all available subcarriers) are disclosed. The scheduled subcarriers may be located in the same or different carriers of a modulation transmitter modulation system, and the pooled transmit power may be allocated or distributed across the scheduled subcarriers of the beam. Modulation symbols or resource elements may be transmitted in accordance with allocated, per-subcarrier power budgets, thereby maximizing the SNIR of signals that are transmitted in the beam via the scheduled subcarriers. Additionally, the allocation of the pooled transmit power to various subcarriers may continuously and/or dynamically vary over time, e.g., based on traffic demands, interference characteristics, etc., as well as based on subsequent scheduling of subcarriers to transmit subsequent modulation symbols or resource elements.
1. A wireless communication system, comprising:
a modulation transmitter configured to wirelessly communicate with a plurality of user terminals via a plurality of carriers, each carrier supporting a plurality of subcarriers; and
a controller configured to:
allocate a per-beam power budget among a total number of resource elements that are scheduled to be in use across the plurality of carriers, the total number of scheduled resource elements being less than a total number of available resource elements across the plurality of carriers, each available resource element corresponding to a respective, single subcarrier over a duration of a respective, single modulation symbol, and the per-beam power budget being a per-beam power limit; and
control resource elements transmitted by the modulation transmitter to communicate with the plurality of user terminals in accordance with the allocation of the per-beam power budget.
2. The wireless communication system of claim 1 , wherein the modulation transmitter forms a plurality of non-overlapping beams radiated by an antenna system, each non-overlapping beam supports the plurality of carriers, and each non-overlapping beam is for establishing a point-to-point connection with a respective user terminal.
3. The wireless communication system of claim 2 , wherein each non-overlapping beam of the plurality of non-overlapping beams is respectively subject to the per-beam power budget.
4. The wireless communication system of claim 3 , wherein a first non-overlapping beam has a first bandwidth allocated to a first user terminal, and a second non-overlapping beam has a second bandwidth allocated to a second user terminal.
5. The wireless communication system of claim 1 , wherein the controller is further configured to:
control a modulation scheme of data to be transmitted via the modulation transmitter to a particular user terminal of the plurality of user terminals based on a channel characteristic corresponding to the particular user terminal, thereby generating a group of modulation symbols; and
allocate at least two modulation symbols included in the group of modulation symbols across multiple subcarriers for transmission to the particular user terminal, wherein the allocated multiple subcarriers are included in the resource elements that are scheduled to be in use across the plurality of carriers.
6. The wireless communication system of claim 5 , wherein the modulation scheme is an OFDM modulation scheme, and each group of modulation symbols is a respective OFDM symbol.
7. The wireless communication system of claim 1 , wherein the respective portions of the per-beam power budget allocated to the scheduled resource elements are an average power budget per scheduled resource element.
8. The wireless communication system of claim 1 , wherein the plurality of carriers is included in an unlicensed frequency band.
9. The wireless communication system of claim 1 , wherein the plurality of carriers is included in a 2.4 GHz frequency band.
10. The wireless communication system of claim 1 , wherein a respective portion of the per-beam power budget is allocated to each scheduled resource element.
11. A method of maximizing the signal-to-interference-plus-noise ratio (SINR) of wireless signals transmitted to a particular user terminal, the method comprising:
allocating, by a controller, a per-beam power budget among a total number of resource elements that are scheduled to be in use across a plurality of carriers included in a beam formed by a modulation transmitter, the total number of scheduled resource elements being less than a total number of available resource elements across the plurality of carriers, each available resource element corresponding to a respective, single subcarrier over a duration of a respective, single modulation symbol, and the per-beam power budget being a per-beam power limit; and
controlling, by the controller in accordance with the allocated per-beam power budget, one or more resource elements transmitted by the modulation transmitter to communicate with the plurality of user terminals.
12. The method of claim 11 , wherein allocating the per-beam power budget among the total number of scheduled resource elements comprises allocating a respective portion of the per-beam power budget to each scheduled resource element.
13. The method of claim 11 ,
further comprising generating at least one resource block for transmission, via more than one scheduled resource element and in accordance with the allocated per-beam power budget, to a particular user terminal of the plurality of user terminals, the generation of the at least one resource block based on a channel characteristic corresponding to the particular user terminal; and
wherein a first subcarrier of the more than one scheduled resource element is included in a first carrier supported by the beam, and a second subcarrier of the more than one scheduled resource element is included in a second carrier supported by the beam.
14. The method of claim 11 , wherein the total number of resource elements that are scheduled to be in use across the plurality of carriers comprises a total number of resource elements that are scheduled to be in use across the plurality of carriers at a first time, and the method further comprises:
determining an updated total number of resource elements that are scheduled to be in use, at a second time subsequent to the first time, across the plurality of carriers included in the beam;
allocating, based on the updated total number of resource elements that are scheduled to be in use across the plurality of carriers at the second time, the per-beam power budget among the resource elements that are scheduled to be in use at the second time; and
controlling, in accordance with the allocated respective portions of the per-beam power budget among the resource elements that are scheduled to be in use at the second time, at least one resource element of the resource elements that are scheduled to be in use at the second time and that are transmitted by the modulation transmitter to communicate data with the plurality of user terminals.
15. The method of claim 11 , wherein the beam formed by the modulation transmitter is included in a plurality of non-overlapping beams formed by the modulation transmitter, and each non-overlapping beam is respectively subject to the per-beam power limit.
16. The method of claim 11 , wherein the modulation transmitter is an OFDM transmitter.
17. The method of claim 11 , wherein one or more respective scheduled resource elements are included in respective OFDM symbols.
18. The method of claim 11 , wherein the plurality of carriers is included in an unlicensed frequency band.
19. The method of claim 11 , wherein the plurality of carriers is included in a 2.4 GHz frequency band.
20. The method of claim 11 , wherein allocating the per-beam power budget among the total number of scheduled resource elements comprises allocating an average power budget per scheduled resource element to each scheduled resource element.