Method and Apparatus for Cancellation of Partially Known Interference Using Transmit Diversity Based Interference Cancellation
First Claim
1. Where a first transmitter transmits desired symbols to a targeted receiver and a second transmitter transmits known interfering symbols, a method of transmit diversity based interference cancellation at the first transmitter comprising:
- receiving scaling information at the first transmitter relating to the targeted receiver;
where the second transmitter respectively transmits first and second interfering symbols in first and second symbol periods or first and second sub-carrier frequencies, transmitting from the first transmitter in the first symbol period or sub-carrier frequency a first transmit diversity combination of a first desired symbol and the second interfering symbol, and transmitting from the first transmitter in the second symbol period or sub-carrier frequency a second transmit diversity combination of the first desired symbol and the first interfering symbol; and
at the first transmitter, forming the first transmit diversity combination as the first desired symbol and the conjugate of the second interfering symbol, both such symbols scaled according to the scaling information, and forming the second transmit diversity combination as the conjugate of the first desired symbol and the conjugate of the first interfering symbol, both such symbols are scaled according to the scaling information.
8 Assignments
0 Petitions
Accused Products
Abstract
In wireless communication networks, potentially significant interference arises at a given targeted receiver because of unrelated transmissions from a neighboring, interfering transmitter. According to apparatuses and methods described and claimed herein, a first transmitter provides for cancellation of partially known interference at a targeted receiver by employing a transmit diversity based interference cancellation method, wherein it transmits diversity combinations of desired and interfering symbols. Correspondingly, the targeted receiver employs diversity combining of the received signals to cancel interference attributable to the interfering symbols.
11 Citations
40 Claims
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1. Where a first transmitter transmits desired symbols to a targeted receiver and a second transmitter transmits known interfering symbols, a method of transmit diversity based interference cancellation at the first transmitter comprising:
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receiving scaling information at the first transmitter relating to the targeted receiver; where the second transmitter respectively transmits first and second interfering symbols in first and second symbol periods or first and second sub-carrier frequencies, transmitting from the first transmitter in the first symbol period or sub-carrier frequency a first transmit diversity combination of a first desired symbol and the second interfering symbol, and transmitting from the first transmitter in the second symbol period or sub-carrier frequency a second transmit diversity combination of the first desired symbol and the first interfering symbol; and at the first transmitter, forming the first transmit diversity combination as the first desired symbol and the conjugate of the second interfering symbol, both such symbols scaled according to the scaling information, and forming the second transmit diversity combination as the conjugate of the first desired symbol and the conjugate of the first interfering symbol, both such symbols are scaled according to the scaling information. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
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16. A transmit diversity based interference cancellation circuit for use where a first transmitter transmits desired symbols to a targeted receiver and a second transmitter transmits known interfering symbols, the transmit diversity based interference cancellation circuit providing transmit diversity based interference cancellation at the first transmitter and comprising one or more processors configured to:
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determine scaling values based receiving scaling information relating to the targeted receiver; form a first transmit diversity combination as the first desired symbol and the conjugate of a second interfering symbol scaled, both such symbols scaled according to the scaling information, and form a second transmit diversity combination as the conjugate of the first desired symbol and the conjugate of a first interfering symbol, both such symbols scaled according to the scaling information; and transmit the first transmit diversity combination in a first symbol period or sub-carrier frequency in which the second transmitter transmits the first interfering symbol, and transmit the second diversity combination in the second symbol period or sub-carrier frequency in which the second transmitter transmits the second interfering symbol. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
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31. A method of transmit diversity based interference cancellation for use at a first transmitter transmitting to a targeted receiver, the method comprising:
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in a first symbol period or sub-carrier, transmitting a first transmit diversity combination signal comprising a combination of a first desired symbol and a second interfering symbol that is transmitted by an interfering second transmitter in a second symbol period or sub-carrier; and in the second symbol period or sub-carrier, transmitting a second transmit diversity combination signal comprising a combination of the first desired symbol and a first interfering symbol that is transmitted by the interfering second transmitter in the first symbol period or sub-carrier; and scaling the second and first interference symbols included in the first and second transmit diversity combination signals according to scaling information relating to the targeted receiver, such that diversity combining of the first and second transmit diversity combination signals by the targeted receiver cancels interference attributable to the first and second interfering symbols from the first desired symbol. - View Dependent Claims (32)
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33. A method of supporting transmit diversity based interference cancellation in a receiver, the method comprising:
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determining a filter as a function of first and second channel models respectively relating the receiver to a first transmitter transmitting a transmit diversity combination signal to the receiver having desired and interfering symbol information, and relating the receiver to a second transmitter transmitting an interfering signal having the interfering symbol information; and detecting desired symbol information by applying the filter to a received signal formed as a first received signal corresponding to a first symbol period or sub-carrier in which the first transmitter transmitted a first transmit diversity combination signal formed from a first desired symbol and a second interfering symbol and the second transmitter transmitted a first interfering symbol, and as a second received signal corresponding to a second symbol period or sub-carrier in which the first transmitter transmitted a second transmit diversity combination signal formed from the first desired symbol and the first interfering symbol and the second transmitter transmitted the second interfering symbol.
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34. For a targeted receiver, a method of supporting transmit diversity based interference cancellation by a first transmitter, the method comprising:
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determining first and second channel models respectively relating the targeted receiver to the first transmitter and to a second transmitter transmitting interfering symbols known to the first transmitter; determining scaling information as a function of the first and second channel models and sending the scaling information to the first transmitter to support transmit diversity based interference cancellation by the first transmitter; determining a filter as a function of the first and second channel models; receiving a first received signal in a first symbol period or sub-carrier and receiving a second received signal in a second symbol period or sub-carrier; said first received signal corresponding to transmission from the first transmitter of a first desired symbol and a second interfering symbol, both such symbols scaled according to the scaling information, and transmission from the second transmitter of a first interfering symbol; said second received signal corresponding to transmission from the first transmitter of the first desired symbol and the first interfering symbol, both such symbols scaled according to the scaling information, and transmission from the second transmitter of the second interfering symbol; and forming a diversity combination of the first and second received signal based on the filter, to thereby cancel interference attributable to the first and second interfering symbols. - View Dependent Claims (35, 36, 37)
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38. A receiver circuit comprising one or more processors configured to:
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determine first and second channel models respectively relating a targeted receiver that includes the receiver circuit to first and second transmitters; determine scaling information as a function of the first and second channel models and send the scaling information to the first transmitter to support transmit diversity based interference cancellation by the first transmitter; determine a filter as a function of the first and second channel models; receive a first received signal in a first symbol period or sub-carrier and receiving a second received signal in a second symbol period or sub-carrier; said first received signal corresponding to transmission from the first transmitter of a first desired symbol and a second interfering symbol, both such symbols scaled according to the scaling information, and transmission from the second transmitter of a first interfering symbol; said second received signal corresponding to transmission from the first transmitter of the first desired symbol and the first interfering symbol, both such symbols scaled according to the scaling information, and transmission from the second transmitter of the second interfering symbol; and form a diversity combination of the first and second received signals based on the filter, to thereby cancel interference attributable to the first and second interfering symbols. - View Dependent Claims (39, 40)
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Specification