Apparatus and method for estimating a plurality of channels
First Claim
1. Apparatus for estimating a plurality of channels from a plurality of distinct transmitting points to a receiving point, wherein an input signal includes a superposition of a first signal based on a first pilot sequence transmittable from a first transmitting point and a second signal based on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence being orthogonal to each other within a predetermined orthogonality range and having a phase shift to each other, comprising:
- a transformer for transforming the input signal into a transformed signal having a set of discrete values, the transformer being operative to translate the phase shift between the first and the second pilot sequence into a delay, so that a first group of the set of the discrete values includes channel information of a first channel from the first transmitting point to the receiving point and that a second group of the set of discrete values includes channel information of a second channel from the second transmitting point to the receiving point;
a selector for selecting the first group from the set of discrete values and for selecting the second group from the set of discrete values to obtain selected groups; and
a processor for determining channel information for the plurality of channels based on the selected groups.
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Accused Products
Abstract
An apparatus for estimating a plurality of channels from a plurality of distinct transmitting points, wherein an input signal includes a super position of signals based on a first pilot sequence transmittable from a first transmitting point and on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence having a phase shift to each other, comprises a transformer, which is operative to translate phase shifts between the first and the second pilot sequence into a delay, so that a first group of a set of discrete values of the transformed signal includes channel information of a first channel and that a second group of a set of discrete values includes channel information of a second channel, a selector for selecting the first group from the set of discrete values and for selecting the second group from the set of discrete values to obtain selected groups, and means for determining channel information for the plurality of channels based on the selected groups. The selection of groups at the output of the transformer for obtaining channel information for the channel allows the construction of a simplified receiver.
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Citations
30 Claims
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1. Apparatus for estimating a plurality of channels from a plurality of distinct transmitting points to a receiving point, wherein an input signal includes a superposition of a first signal based on a first pilot sequence transmittable from a first transmitting point and a second signal based on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence being orthogonal to each other within a predetermined orthogonality range and having a phase shift to each other, comprising:
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a transformer for transforming the input signal into a transformed signal having a set of discrete values, the transformer being operative to translate the phase shift between the first and the second pilot sequence into a delay, so that a first group of the set of the discrete values includes channel information of a first channel from the first transmitting point to the receiving point and that a second group of the set of discrete values includes channel information of a second channel from the second transmitting point to the receiving point;
a selector for selecting the first group from the set of discrete values and for selecting the second group from the set of discrete values to obtain selected groups; and
a processor for determining channel information for the plurality of channels based on the selected groups. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
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25. Apparatus for providing a plurality of different pilot sequences to be used for channel estimation, comprising:
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a calculator for calculating an ith value Xi(μ
) of a pilot sequence to be transmitted by a μ
th transmitting point of NT transmitting points using the following equation;
Xi(μ
)=e−
j2π
(i−
1)(μ
−
1)/NT Xi(s)wherein NT denotes a number of transmitting points and wherein NT is greater than or equal to 3; and
wherein Xi(s) denotes an ith, value of a scrambling sequence, the length of the scrambling sequence being equal to the length of the pilot sequence.
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26. Apparatus for providing a number of different pilot sequences to be used for channel estimation, comprising:
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a generator for generating a Hadamard matrix having a number of columns, the number of columns corresponding to the number of different pilot sequences;
a calculator for calculating the different pilot sequences based on the columns of the Hadamard matrix, wherein each pilot sequence is derived from another column of the Hadamard matrix.
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27. Method for estimating a plurality of channels from a plurality of distinct transmitting points to a receiving point, wherein an input signal includes a superposition of a first signal based on a first pilot sequence transmittable from a first transmitting point and a second signal based on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence being orthogonal to each other within a predetermined orthogonality range and having a phase shift to each other, comprising the following steps:
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transforming the input signal into a transformed signal having a set of discrete values by translating the phase shift between the first and the second pilot sequence into a delay, so that a first group of the set of discrete values includes channel information of a first channel from the first transmitting point to the receiving point and that a second group of the set of discrete values includes channel information of a second channel from the second transmitting point to the receiving point;
selecting the first group from the set of discrete values and selecting the second group from the set of discrete values to obtain selected groups;
determining channel information for the plurality of channels on the basis of the selected groups.
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28. Method for providing a plurality of different pilot sequences to be used for channel estimation, comprising the following steps:
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calculating an ith value Xi(μ
) of a pilot sequence to be transmitted by a μ
th transmitting point of NT transmitting points using the following equation;
Xi(μ
)=e−
j2π
(i−
1)(μ
−
1)/NT Xi(s)wherein NT denotes a number of transmitting points and wherein Nt is greater than or equal than 3; and
wherein Xi(s) denotes an ith value of a scrambling sequence, the length of which being equal to the length of the pilot sequences.
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29. Method for providing a number of different pilot sequences to be used for channel estimation, comprising the following steps:
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generating a Hadamard matrix having a number of columns, the number of columns corresponding to the number of different pilot sequences;
calculating the different pilot sequences based on the columns of the Hadamard matrix, wherein each pilot sequence is derived from another column of the Hadamard matrix.
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30. Computer program having a program code for performing the method for estimating a plurality of channels from a plurality of distinct transmitting points to a receiving point, wherein an input signal includes a superposition of a first signal based on a first pilot sequence transmittable from a first transmitting point and a second signal based on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence being orthogonal to each other within a predetermined orthogonality range and having a phase shift to each other, comprising the following steps:
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transforming the input signal into a transformed signal having a set of discrete values by translating the phase shift between the first and the second pilot sequence into a delay, so that a first group of the set of discrete values includes channel information of a first channel from the first transmitting point to the receiving point and that a second group of the set of discrete values includes channel information of a second channel from the second transmitting point to the receiving point;
selecting the first group from the set of discrete values and selecting the second group from the set of discrete values to obtain selected groups;
determining channel information for the plurality of channels on the basis of the selected groups, the method for providing a plurality of pilot sequences to be used for channel estimation, comprising the following steps;
calculating an ith value Xi(μ
) of a pilot sequence to be transmitted by a μ
th transmitting point of NT transmitting points using the following equation;
Xi(μ
)=e−
j2π
(i−
1)(μ
−
1)/NT Xi(s)wherein NT denotes a number of transmitting points and wherein Nt is greater than or equal than 3; and
wherein Xi(s) denotes an ith value of a scrambling sequence, the length of which being equal to the length of the pilot sequences, the method for providing a plurality of pilot sequences to be used for channel estimation, comprising the following steps;
generating a Hadamard matrix having a number of columns, the number of columns corresponding to the number of different pilot sequences;
calculating the different pilot sequences based on the columns of the Hadamard matrix, wherein each pilot sequence is derived from another column of the Hadamard matrix, when the program runs on a computer.
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Specification