Methods and apparatus for downlink PDSCH power setting
First Claim
1. A method for calculating traffic-to-pilot ratios at a wireless terminal, the method comprising the steps of:
- establishing a table for calculating traffic-to-pilot ratios at the wireless terminal in a communication system, with the wireless terminal having a plurality of OFDM symbols available for transmission, a subset of the OFDM symbols being used for transmitting reference signals;
receiving a reference signal (RS) overhead ratio η
RS and a traffic-to-pilot ratio PB,k/PRS for certain Orthogonal Frequency Division Multiplexing (OFDM) symbols at the wireless terminal, with PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; and
calculating traffic-to-pilot ratios across different transmission antennas and different OFDM symbols in dependence upon the calculation table and the number of available transmission antennas in the wireless terminal.
1 Assignment
0 Petitions
Accused Products
Abstract
Methods and apparatus for transmitting power setting information in a downlink Physical Downlink Shared Channel (PDSCH) in a communication system. In this communication system, a plurality of methods for calculating traffic-to-pilot ratios (T2P) are established. In addition, a mapping scheme between a plurality of overhead signals and a plurality of reference signal (RS) overhead ratios, ηRS, and the plurality of T2P calculation methods is established. A user-specific T2P ratio PB,k/PRS for certain OFDM symbols, a RS overhead ratio ηRS and a calculation method selected from the plurality of T2P calculation methods are assigned to a wireless terminal. Then, an overhead signal corresponding to both of the assigned RS overhead ratio ηRS and the assigned T2P calculation method is selected in accordance with the mapping scheme and is transmitted to the wireless terminal. In addition, the user-specific traffic-to-pilot ratio PB,k/PRS is transmitted to the wireless terminal. The wireless terminal may calculate the traffic-to-pilot ratios across different transmission antennas and different OFDM symbols in dependence upon the received traffic-to-pilot ratio PB,k/PRS, and the RS overhead ratio and the T2P calculation method indicated by the RS overhead signal.
34 Citations
21 Claims
-
1. A method for calculating traffic-to-pilot ratios at a wireless terminal, the method comprising the steps of:
-
establishing a table for calculating traffic-to-pilot ratios at the wireless terminal in a communication system, with the wireless terminal having a plurality of OFDM symbols available for transmission, a subset of the OFDM symbols being used for transmitting reference signals; receiving a reference signal (RS) overhead ratio η
RS and a traffic-to-pilot ratio PB,k/PRS for certain Orthogonal Frequency Division Multiplexing (OFDM) symbols at the wireless terminal, with PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; andcalculating traffic-to-pilot ratios across different transmission antennas and different OFDM symbols in dependence upon the calculation table and the number of available transmission antennas in the wireless terminal. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method for transmitting power setting information to a wireless terminal, the method comprising the steps of:
-
establishing a plurality of methods for calculating traffic-to-pilot ratios (T2P); establishing a mapping scheme between a plurality of overhead signals, R_ovhd, and a plurality of reference signal (RS) overhead ratios, η
RS, and the plurality of T2P calculation methods;assigning a user-specific traffic-to-pilot ratio PB,k/PRS for certain Orthogonal Frequency Division Multiplexing (OFDM) symbols to the wireless terminal, with the wireless terminal having a plurality of OFDM symbols available for data transmission, a subset of the OFDM symbols being used for transmitting reference signals, PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; assigning a RS overhead ratio η
RS and a calculation method selected from the plurality of T2P calculation methods to the wireless terminal; andtransmitting the user-specific traffic-to-pilot ratio PB,k/PRS, and an overhead signal, R_ovhd, corresponding to both of the assigned RS overhead ratio η
RS and the assigned T2P calculation method in accordance with the mapping scheme, to the wireless terminal. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method for calculating traffic-to-pilot ratios, the method comprising the steps of:
-
receiving a reference signal (RS) overhead signal indicating both of a RS overhead ratio and a method for calculating traffic-to-pilot (T2P) ratios at a wireless terminal in a communication system; receiving a certain traffic-to-pilot ratio PB,k/PRS, with the wireless terminal having a plurality of OFDM symbols available for data transmission, a subset of the OFDM symbols being used for transmitting reference signals, PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; and calculating the traffic-to-pilot ratios across different transmission antennas and different OFDM symbols in dependence upon the received traffic-to-pilot ratio PB,k/PRS, and the RS overhead ratio and the T2P calculation method indicated by the RS overhead signal.
-
-
18. A method for transmitting a power setting information to a wireless terminal, the method comprising the steps of:
-
assigning a plurality of traffic-to-pilot ratios PA,k/PRS and PB,k/PRS for different Orthogonal Frequency Division Multiplexing (OFDM) symbols and different transmission antennas to the wireless terminal, with the wireless terminal having a plurality of OFDM symbols available for data transmission, a subset of the OFDM symbols being used for transmitting reference signals (RS), PA,k being the Energy Per Resource Element (EPRE) power assigned on the RS OFDM symbols, PB,k being the EPRE power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; and transmitting the assigned traffic-to-pilot ratios PA,k/PRS and PB,k/PRS explicitly to the wireless terminal.
-
-
19. A wireless terminal in a communication system, comprising:
-
a memory unit storing a plurality of methods for calculating traffic-to-pilot ratios (T2P), and storing a mapping scheme between a plurality of overhead signals, and a plurality of reference signal (RS) overhead ratios and the plurality of T2P calculation methods; a power setting unit assigning a user-specific traffic-to-pilot ratio PB,k/PRS, a RS overhead ratio, η
RS, and a calculation method selected from the plurality of T2P calculation methods to a second wireless terminal, with the second wireless terminal having a plurality of OFDM symbols available for data transmission, a subset of the OFDM symbols being used for transmitting reference signals, PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; andat least one antenna transmitting an overhead signal corresponding to both of the assigned RS overhead ratio η
RS and the assigned T2P calculation method in accordance with the mapping scheme, and the user-specific traffic-to-pilot ratio PB,k/PRS, to the second wireless terminal.
-
-
20. A wireless terminal in a communication system, comprising:
-
a memory unit storing a plurality of methods for calculating traffic-to-pilot ratios (T2P), and storing a mapping scheme between a plurality of overhead signals, and a plurality of reference signal (RS) overhead ratios and the plurality of T2P calculation methods; at least one antenna receiving an overhead signal and a certain traffic-to-pilot ratio PB,k/PRS with the wireless terminal having a plurality of OFDM symbols available for data transmission, a subset of the OFDM symbols being used for transmitting reference signals, PB,k being the Energy Per Resource Element (EPRE) power assigned on the non-RS OFDM symbols, and PRS being the RS power per subcarrier; and a power setting unit calculating the traffic-to-pilot ratios across different transmission antennas and different OFDM symbols in dependence upon the received traffic-to-pilot ratio PB,k/PRS, and the RS overhead ratio and the T2P calculation method corresponding to the RS overhead signal.
-
-
21. A method for allocating transmit power at a wireless terminal,
the wireless terminal having a plurality of OFDM symbols available for transmission, and a subset of the OFDM symbols being used for transmitting reference signals, with the method comprising the steps of: -
receiving a semi-static parameter from a broadcast channel, with the semi-static parameter being denoted by PB; and assigning equal Energy Per Resource Element (EPRE) ratios among a first set of resource elements in the OFDM symbols not transmitting the reference signals, with the ratio of the traffic data EPRE to pilot EPRE (T2P) among the first set of resource elements being denoted by ρ
A;assigning equal EPRE ratios among a second set of resource elements in the OFDM symbols transmitting the reference signals, with the ratio off traffic data EPRE to pilot EPRE (T2P) among the second set of resource elements being denoted by ρ
B, with the ratio of ρ
B to ρ
A being determined in dependence upon one of a semi-static parameter PB, and a semi-static pilot power overhead parameter, η
RS, based on the following table;One Two and Four η
RSPB Antenna Port Antenna Ports 1/6 0 1 5/4 1/3 1 4/5 1 3/6 2 3/5 3/4 4/6 3 2/5 1/2
-
Specification