Pilot pattern design for an OFDM system
View Patent ↗The present invention relates to a transmitting device and a receiving device in a wireless orthogonal frequency division multiplex (OFDM) communication system with space time transmit diversity (STTD). Further, the present invention relates to a channel estimation method for performing a channel estimation in such a wireless communication system, in which the transmitting device comprises a first and a second antenna for transmitting signals with space time transmit diversity. The first and the second antenna means are arranged spaced apart from each other in a space diversity arrangement, whereby first and second pilot symbols are transmitted via said first and said second antenna means, respectively. Some of the second pilot symbols are orthogonal to corresponding ones of the first pilot symbols, so that a channel estimation to separately determine the transmission quality of signals transmitted from the first and the second antenna means, respectively, can be performed in a receiving device which receives the signals with only one single antenna.
1. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so that a first pilot symbol pattern in a frequency dimension contains at least said first type pilot symbol to be transmitted by using a predefined subcarrier and second type pilot symbol to be transmitted by using another predefined subcarrier,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
2. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so that a first pilot symbol pattern in a frequency dimension contains at least said first type pilot symbol to be transmitted by using a predefined subcarrier and second type pilot symbol to be transmitted by using another predefined subcarrier,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
3. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are allocated respectively in a frequency dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
4. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are allocated respectively in a frequency dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
5. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol or a second type pilot symbol having an inverted value of said first type pilot symbol to said generated pilot symbols in a frequency dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
6. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol to said generated pilot symbols in a frequency dimension or a second type pilot symbol having an inverted value of said first type pilot symbol to said generated pilot symbols in a frequency dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
7. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to create a first pilot symbol pattern in a frequency dimension comprising at least a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol, wherein said first pilot symbol pattern assigned to one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
8. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to create a first pilot symbol pattern in a frequency dimension comprising at least a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol,
wherein said first pilot symbol pattern assigned to one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
9. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so that a first pilot symbol pattern in a time dimension comprises at least said first and second type pilot symbols to be transmitted at different timepoints respectively,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
10. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so that a first pilot symbol pattern in a time dimension comprises at least said first and second type pilot symbols to be transmitted at different timepoints respectively,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
11. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are regularly allocated in a time dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
12. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are regularly allocated in a time dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
13. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol or a second type pilot symbol having an inverted value of said first type pilot symbol to said generated pilot symbols in a time dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
14. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol or a second type pilot symbol having an inverted value of said first type pilot symbol to said generated pilot symbols in a time dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
15. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to generate either a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol in a time dimension as a type of said generated pilot symbols, wherein a first pilot symbol pattern, comprising said first and second type pilot symbols allocated in the time dimension, which is assigned to one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern which is assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
16. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to generate either a first type pilot symbol and a second type pilot symbol having an inverted value of said first type pilot symbol in a time dimension as a type of said generated pilot symbols, wherein a first pilot symbol pattern, comprising said first and second type pilot symbols allocated in the time dimension, which is assigned to one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern which is assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
17. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so that a first pilot symbol pattern in a frequency dimension contains at least said first type pilot symbol to be transmitted by using a predefined subcarrier and second type pilot symbol to be transmitted by using other predefined subcarrier,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
18. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so that a first pilot symbol pattern in a frequency dimension contains at least said first type pilot symbol to be transmitted by using a predefined subcarrier and second type pilot symbol to be transmitted by using other predefined subcarrier,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
19. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are allocated respectively in a frequency dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
20. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are allocated respectively in a frequency dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
21. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol to said generated pilot symbols in a frequency dimension or a second type pilot symbol being orthogonal to said first type pilot symbol to said generated pilot symbols in a frequency dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
22. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol to said generated pilot symbols in a frequency dimension or a second type pilot symbol being orthogonal to said first type pilot symbol to said generated pilot symbols in a frequency dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
23. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to create a first pilot symbol pattern in a frequency dimension comprising at least a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol,
wherein said first pilot symbol pattern assigned to one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
24. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to create a first pilot symbol pattern in a frequency dimension comprising at least a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol, wherein said first pilot symbol pattern assigned to one of said plurality of transmission antennas has a different pattern from a second pilot symbol pattern assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
25. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so that a first pilot symbol pattern in a time dimension comprises at least said first and second type pilot symbols to be transmitted at different timepoints respectively,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
26. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols respectively by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so that a first pilot symbol pattern in a time dimension comprises at least said first and second type pilot symbols to be transmitted at different timepoints respectively,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
27. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are regularly allocated in a time dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
28. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system having a plurality of transmission antennas, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via said plurality of transmission antennas,
wherein said symbol generating means generates a first type pilot symbol and a second type pilot symbol being orthogonal to said first type pilot symbol so as to create a first pilot symbol pattern in where said first and second type pilot symbols are regularly allocated in a time dimension,
wherein said first pilot symbol pattern to be transmitted by using one of said plurality of transmission antennas is different from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
29. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol to said generated pilot symbols in a time dimension or a second type pilot symbol being orthogonal to said first type pilot symbol to said generated pilot symbols in a time dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
30. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means assigns either a first type pilot symbol to said generated pilot symbols in a time dimension or a second type pilot symbol being orthogonal to said first type pilot symbol to said generated pilot symbols in a time dimension so that a first pilot symbol pattern comprising said first and second type pilot symbols to be transmitted by using one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern to be transmitted by using another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
31. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to generate either a first type pilot symbol as a type of said generated pilot symbols or a second type pilot symbol being orthogonal to said first type pilot symbol in a time dimension as a type of said generated pilot symbols,
wherein a first pilot symbol pattern, comprising said first and second type pilot symbols allocated in the time dimension, which is assigned to one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern which is assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in the time dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.
32. A transmitting device for transmitting data symbols and pilot symbols in an OFDM transmission system, the device comprising
symbol generating means for generating said data symbols and said pilot symbols,
means for transmitting said data symbols and pilot symbols by using a plurality of subcarriers of said OFDM transmission system via a plurality of transmission antennas,
wherein said symbol generating means is designed to generate either a first type pilot symbol as a type of said generated pilot symbols or a second type pilot symbol being orthogonal to said first type pilot symbol in a time dimension as a type of said generated pilot symbols,
wherein a first pilot symbol pattern, comprising said first and second type pilot symbols allocated in the time dimension, which is assigned to one of said plurality of transmission antennas is a different pattern from a second pilot symbol pattern which is assigned to another transmission antenna, and
wherein at least some pairs of first pilot symbols comprised in said first pilot symbol pattern and being adjacent in a frequency dimension are respectively orthogonal to the corresponding pairs of second pilot symbols comprised in said second pilot pattern.