Bidirectional digital wireless system transmitting and receiving asymmetric frames

• US 20030142649A1
• Filed: 01/29/2003
• Published: 07/31/2003
• Est. Priority Date: 01/30/2002
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Taniguchi, Shohei
• Granted Patent: US 7,317,713 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04B 7/2656 for structure of frame, burst

Abstract

Herein disclosed is a bidirectional digital wireless system transmitting and receiving asymmetric transmission frames comprising: a mobile station for transmitting a plurality of uplink transmission frames each including a guard frame portion and a data frame portion carrying a main information segment; and a base station for receiving the uplink transmission frames, and generating and transmitting a plurality of downlink transmission frames each including an information frame element carrying a subsidiary information segment to the mobile station, whereby the base station is operative to divide the information frame element into a predetermined number of information frame portions respectively corresponding to the guard frame portions of the uplink transmission frame with respect to time length, and generate and transmit a plurality of downlink transmission frames each including the information frame portions collectively forming an information frame element carrying a subsidiary information segment to the mobile station.

Claims

1. A bidirectional digital wireless system using asymmetric transmission frames comprising:

a mobile station for generating and transmitting a plurality of uplink transmission frames each including a guard frame portion and a data frame portion carrying a main information segment in a time division demultiplexing manner;

said guard frame portion and said data frame portion being separated from each other with respect to time length; and

a base station for receiving said uplink transmission frames, and generating and transmitting a plurality of downlink transmission frames each including an information frame element carrying a subsidiary information segment to said mobile station with reference to said uplink transmission frames in said time division demultiplexing manner, whereby

said base station is operative to divide said information frame element into a predetermined number of information frame portions respectively corresponding to said guard frame portions of said uplink transmission frames with respect to time length, and generate and transmit a plurality of downlink transmission frames each including said information frame portions collectively forming an information frame element carrying a subsidiary information segment to said mobile station, and

said mobile station is operative to receive said downlink transmission frame in a time division multiplexing manner so as to sequentially extract said information frame portions collectively forming said information frame element, and perform said subsidiary information segment in accordance with said information frame element thus extracted to ensure reliable and efficient communication with said base station.

2. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 1, in which

said information frame element carrying said subsidiary information segment includes an index frame element indicative of a category of said subsidiary information segment and a state frame element indicative of a state of said subsidiary information segment, said index frame element and said state frame element respectively have frame lengths,

said mobile station and said base station respectively comprise storage units each for storing a reference table showing said frame lengths of said state frame elements in association with said frame lengths of said index frame elements, and

said base station is operative to generate and transmit a plurality of downlink transmission frames each including an information frame element including an index frame element and a state frame element with reference to-said reference table stored in said storage unit, whereby

said mobile station is operative to receive said downlink transmission frames in said time division multiplexing manner so as to sequentially extract said information frame portions collectively forming said information frame element, detect said index frame element, identify said frame lengths of, and detect said index frame element and said state frame element with reference to said reference table stored in said storage unit, and perform said subsidiary information segment in accordance with said index frame element and said state frame element thus identified and detected.

3. A bidirectional digital wireless system using asymmetric transmission frames as set forth in any one of claims 1 and 2, in which

said base station comprises:

a downlink unique word generating unit for generating a downlink unique word signal carrying frame synchronization information; and

a downlink information generating unit for generating a pilot signal indicative of transmit power control information, and superimposing said downlink unique word signal on said pilot signal to output a pilot frame element carrying said transmit power control information and said frame synchronization information,

said base station is operative to generate and transmit a plurality of downlink transmission frames each including said information frame portions each of which contains said pilot frame element to said mobile station with reference to said uplink transmission frames.

4. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 3, in which

said mobile station is operative to receive said downlink transmission frames each including said information frame portions each of which contains said pilot frame element carrying said transmit power control information and said frame synchronization information from said base station in a time division multiplexing manner so as to sequentially extract said pilot frame element, and perform a transmit power control function and a frame synchronization function in accordance with each of said pilot frame elements to ensure reliable and efficient communication with said base station.

5. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 3, in which

said base station is operative to divide said pilot frame element into a predetermined number of pilot frame fragments collectively forming said pilot frame element so as to generate and transmit a plurality of downlink transmission frames each including said information frame portions collectively forming said pilot frame element carrying said transmit power control information and said frame synchronization information.

6. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 5, in which

said mobile station is operative to receive said downlink transmission frames each including said information frame portions collectively forming said pilot frame element carrying said transmit power control information and said frame synchronization information from said base station in a time division multiplexing manner so as to sequentially extract said information frame portions, collectively reconstruct said pilot frame element, and perform a transmit power control function and a frame synchronization function in accordance with each pilot frame element to ensure reliable and efficient communication with said base station.

7. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 3, in which

said base station is operative to divide said pilot frame element into a predetermined number of pilot frame fragments collectively forming said pilot frame element, and respectively attach unique numbers to said pilot frame fragments so as to generate and transmit a plurality of downlink transmission frames each including said information frame portions having respective unique numbers, and collectively forming said pilot frame element carrying said transmit power control information and said frame synchronization information.

8. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 7, in which

said mobile station is operative to receive said downlink transmission frames each including said information frame portions having respective unique numbers, and collectively forming said pilot frame element carrying said transmit power control information and said frame synchronization information from said base station in a time division multiplexing manner so as to sequentially extract said information frame portions, collectively reconstruct said pilot frame element with reference to said respective unique numbers, and perform a transmit power control function and a frame synchronization function in accordance with each pilot frame element to ensure reliable and efficient communication with said base station.

9. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 3, in which

said base station is operative to generate a pilot frame element carrying said transmit power control information and said frame synchronization information for each of said downlink transmission frames, and divide said pilot frame element into a predetermined number of pilot frame fragments collectively forming said pilot frame element so as to generate and transmit a plurality of downlink transmission frames each including said information frame portions collectively forming said pilot frame element carrying said transmit power control information and said frame synchronization information.

10. A bidirectional digital wireless system using asymmetric transmission frames as set forth in any one of claims 1 and 2, in which

said base station comprises:

a downlink preamble signal generating unit for generating a downlink preamble signal carrying clock synchronizing information; and

a downlink information generating unit for generating a pilot signal indicative of transmit power control information, and superimposing said downlink preamble signal on said pilot signal to output a preamble frame element carrying said transmit power control information and said clock synchronization information,

said base station is operative to generate and transmit a plurality of downlink transmission frames each including said information frame portions each of which contains said preamble frame element to said mobile station with reference to said uplink transmission frames.

11. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 10, in which

said mobile station is operative to receive said downlink transmission frames each including said information frame portions each of which contains said preamble frame element carrying said transmit power control information and said clock synchronization information from said base station in a time division multiplexing manner so as to sequentially extract said preamble frame element, and perform a transmit power control function and a clock synchronization function in accordance with each of said preamble frame element to ensure reliable and efficient communication with said base station.

12. A bidirectional digital wireless system using asymmetric transmission frames as set forth in any one of claims 1 and 2, in which

said base station comprises:

a system state managing unit for generating a downlink information signal carrying a subsidiary information segment, and

a downlink information generating unit for performing error correcting coding and time diversity transmission processes to said downlink information signal generated by said system state managing unit to generate a predetermined number of data frame portions to be time-divided into a plurality of data frame segments respectively corresponding to said guard frame portions of said uplink transmission frames, and output a downlink transmission frame including said data frame segments;

said base station is operative to generate and transmit a plurality of downlink transmission frames each including said data frame segments, whereby

said mobile station is operative to receive said downlink transmission frames including said data frame segments in a time division multiplexing manner so as to sequentially extract said predetermined number of data frame portions,

perform time diversity receiving and error correcting decoding processes to said data frame portions thus extracted to select a data frame portion which agrees with a majority of said data frame portions from among said data frame portions thus extracted, and assume that said data frame portion thus selected accurately carries said subsidiary information segment from among said data frame portions, and

perform said subsidiary information segment in accordance with said data frame portion thus extracted and selected to ensure reliable and efficient communication with said base station.

13. A bidirectional digital wireless system using asymmetric transmission frames as set forth in any one of claims 1 and 2, in which

said base station comprises:

a system state managing unit for generating a downlink information signal carrying a subsidiary information segment, and

a downlink information generating unit for performing error detecting coding and time diversity transmission processes to said downlink information signal generated by said system state managing unit to generate a predetermined number of data frame portions to be time-divided into a plurality of data frame segments respectively corresponding to said guard frame portions of said uplink transmission frames, and output a downlink transmission frame including said data frame segments;

said base station is operative to generate and transmit a plurality of downlink transmission frames each including said data frame segments, whereby

said mobile station is operative to receive said downlink transmission frames including said data frame segments in a time division multiplexing manner so as to sequentially extract said predetermined number of data frame portions,

perform time diversity receiving and error detecting decoding processes to said data frame portions thus extracted to judge whether a predetermined number of said data frame portions are equal to one another or not, select a data frame portion which agrees with a majority of said data frame portions from among said data frame portions thus extracted, and assume that said data frame portion accurately carries said subsidiary information segment when it is judged that said predetermined number of said data frame portions are equal to one another, and perform said subsidiary information segment in accordance with said data frame portion thus extracted and selected to ensure reliable and efficient communication with said base station, and

discard said data frame portions when it is judged that said predetermined number of said data frame portions are not equal to one another.

14. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 12, in which

said downlink information generating unit of said base station is operative to perform said diversity transmission process for a variable number of times to generate a number of data frame portions to be time-divided into a plurality of data frame segments respectively corresponding to said guard frame portions of said uplink transmission frames, and output a downlink transmission frame including said data frame segments, said number of data frame portions being specific to each of said downlink transmission frames,

said mobile station is operative to receive said downlink transmission frames including said data frame segments in a time division multiplexing manner so as to sequentially extract said number of data frame portions,

perform time diversity receiving and error processing decoding processes to said data frame portions thus extracted to select a data frame portion which agrees with a majority of said data frame portions from among said data frame portions, and

perform said subsidiary information segment in accordance with said data frame portion thus extracted and selected to ensure reliable and efficient communication with said base station.

15. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 14, in which

said mobile station is operative to generate a diversity signal indicative of a number of times to be performed for time diversity, generate and transmit an uplink transmission frame carrying a main information segment including said diversity signal indicative of said number of times.

16. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 15, in which

said base station is operative to receive said uplink transmission frame carrying a main information segment including said diversity signal indicative of said number of times from said mobile station to extract said diversity signal from said uplink transmission frame, and

said downlink information generating unit of said base station is operative to perform said time diversity transmission process for said number of times indicated by said diversity signal to generate said number of data frame portions to be time-divided into a plurality of data frame segments respectively corresponding to said guard frame portions of said uplink transmission frames, and output a downlink transmission frame including said data frame segments.

17. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 15, in which

said mobile station is operative to generate and transmit a plurality of uplink transmission frames carrying a main information segment including said diversity signal indicative of said number of times, said plurality of uplink transmission frames corresponding to a downlink transmission frame with respect to time length.

18. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 15, in which

said mobile station is operative to generate a diversity signal indicative of a number of times to be performed for time diversity in said base station, performs a time diversity transmission process to said diversity signal to output a predetermined number of data frame elements to be time-divided into a predetermined number of data frame segments collectively containing said data frame elements carrying said diversity signal, and transmit said uplink transmission frame including said data frame segments.

19. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 18, in which

said base station is operative to receive said uplink transmission frame including said data frame segments carrying said diversity signal from said mobile station in a time division multiplexing manner so as to sequentially extract said data frame elements collectively contained in predetermined number of data frame segments,

perform a time diversity receiving process to said data frame elements thus extracted,

select a data frame element which agrees with a majority of said data frame elements from among said data frame elements thus extracted, and assume that data frame element thus selected accurately carries said diversity signal from among said data frame elements by majority, and

perform said time diversity transmission process in accordance with said diversity signal indicative of a number of times to be performed for time diversity in said base station.

20. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 12, in which

said mobile station is operative to receive said downlink transmission frames including said data frame segments in a time division multiplexing manner so as to count a number of times to be performed for a time diversity receiving process,

said mobile station comprises a storage unit for storing said number of times to be performed for a time diversity receiving process thus counted, whereby

said mobile station is operative to receive said downlink transmission frames including said data frame segments in a time division multiplexing manner so as to count a number of times to be performed for a time diversity receiving process,

compare said number of times to be performed for a time diversity receiving process thus currently counted with said number previously counted and stored in said storage unit, and

determine a number of times to be performed for a subsequent time diversity transmission process in said base station on the basis of a result of comparison performed between said number of times to be performed for a time diversity receiving process currently counted with said number previously counted and stored in said storage unit.

21. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 20, in which

said mobile station is operative to

judge whether said number of times to be performed for a time diversity receiving process thus currently counted is equal to said number of times to be performed for a time diversity receiving process previously counted and stored in said storage unit,

determine said number of times to be performed for a time diversity receiving process previously counted and stored in said storage unit to be a number of times to be performed for a subsequent time diversity transmission process in said base station when it is judged that said number of times to be performed for a time diversity receiving process thus currently counted is equal to said number of times to be performed for a time diversity receiving process previously counted and stored in said storage,

judge whether said number of times to be performed for a time diversity receiving process thus currently counted is greater than said number previously counted and stored in said storage unit when it is judges that said number of times to be performed for a time diversity receiving process thus currently counted is not equal to said number of times to be performed for a time diversity receiving process previously counted and stored in said storage,

determine a number of times greater than said time diversity receiving process stored in said storage to be a number of times to be performed for a subsequent time diversity transmission process in said base station when it is judges that said number of times to be performed for a time diversity receiving process thus currently counted is greater said number of times to be performed for a time diversity receiving process previously counted and stored in said storage, and

determine a number of times less than said time diversity receiving process stored in said storage to be a number of times to be performed for a subsequent time diversity transmission process in said base station when it is judges that said number of times to be performed for a time diversity receiving process thus currently counted is not greater said number of times to be performed for a time diversity receiving process previously counted and stored in said storage.

22. A bidirectional digital wireless system using asymmetric transmission frames as set forth in claim 12, in which

said mobile station comprises a receive level detecting unit for detecting a received power level,

said mobile station is operative to calculate a distance between said mobile station and said base station with reference to said received power level detected by said receive level detecting unit, and

determine a number of times to be performed for a subsequent time diversity transmission process in said base station on the basis of said distance thus calculated.