| Sonstiges: |
- Nachgewiesen in: USPTO Patent Grants
- Sprachen: English
- Patent Number: 7,295,606
- Publication Date: November 13, 2007
- Appl. No: 10/683405
- Application Filed: October 14, 2003
- Assignees: Mitsubishi Denki Kabushiki Kaisha (Tokyo, JP)
- Claim: 1. A method for transmitting data symbols to or from users of an ultra bandwidth telecommunication system, each user (u) of said system being associated with a specific time hopping pattern consisting of a plurality (N s , N b) of integers (c j c), a signal including said data symbols transmitted to or from a user consisting of sequences of frames, each integer of said specific time hopping pattern being associated with a corresponding frame and each frame containing a pulse time-shifted from the beginning thereof by an amount (c j u T c) determined by said associated integer, comprising: pulse position modulating one of said sequences by one or a plurality (n b) of said data symbols to be transmitted to or from said user; based on a pseudo-random sequence specific to said user, determining a time at which said sequence is to be transmitted; time-shifting the time at which the sequence is transmitted from an end of a preceding sequence by a time shift (θ m u), said time shift being determined as a function of a number of a pseudo-random sequence specific to said user; and transmitting said sequence to or from said user at the determined time.
- Claim: 2. The method according to claim 1 , further comprising: time-shifting the time at which the sequence is transmitted from a reference synchronisation signal common to all users by a time shift (θ m u), said time shift being determined as a function of a number of a pseudo-random sequence specific to said user.
- Claim: 3. The method according to claim 1 , further comprising: time-shifting the time at which the sequence is transmitted by a time shift from a synchronisation signal generated locally by said user, said time shift (θ m u) being determined as a function of a number of a pseudo-random sequence specific to said user.
- Claim: 4. The method according to claim 2 , further comprising: obtaining a new time shift from said pseudo-random sequence for every sequence of a user.
- Claim: 5. The method according to claim 1 , further comprising: obtaining a new time shift from said pseudo-random sequence for every sequence of a user.
- Claim: 6. The method according to any of claim 3 , further comprising: obtaining a new time shift from said pseudo-random sequence for every sequence of a user.
- Claim: 7. The method according to claim 2 , further comprising: obtaining a new time shift from said pseudo-random sequence for each sequence of a user out of a predetermined plurality thereof.
- Claim: 8. The method according to claim 1 , further comprising: obtaining a new time shift from said pseudo-random sequence for each sequence of a user out of a predetermined plurality thereof.
- Claim: 9. The method according to claim 3 , further comprising: obtaining a new time shift from said pseudo-random sequence for each sequence of a user out of a predetermined plurality thereof.
- Claim: 10. The method according to any one of claims 1 - 2 and 3 - 9 , further comprising: chosing time hopping patterns of the different users such that an average value (γ) of a squared cross-correlation function of any pair of sequences of distinct users (u,u′) is equal or substantially equal to a predetermined minimum value (γ min).
- Claim: 11. The method according to any one of claims 1 - 2 and 3 - 9 , further comprising: determining a plurality of integers of the time hopping pattern associated with a user by the following expression: c j u =(u +α).(j +β) mod p where u is an integer indexing said user, j is an integer indexing a frame of a sequence of said user, α,β are predetermined integers, and p is a prime number.
- Claim: 12. The method according to any one of claims 1 - 2 and 3 - 9 , further comprising: determining a plurality of integers of the time hopping pattern associated to a user by the following expression: c j u =(u +α) (j+β) mod p where u is an integer indexing said user, j is an integer indexing a frame of a sequence of said user, α,β are predetermined integers, and p is a prime number.
- Claim: 13. A transmitter for transmitting data symbols to or from at least one user of an ultra bandwidth telecommunication system, each user (u) of said system being associated with a specific time hopping pattern consisting of a plurality (N s , N b) of integers (c j u), said transmitter comprising: means for generating sequences of frames, each integer of said specific time hopping pattern being associated with a corresponding frame of said sequence; means for shifting a pulse of said corresponding frame of said sequence by an amount of time (c j u T c) determined by said associated integer; and means for modulating positions of pulses of a sequence by one or a plurality of data symbols to be transmitted to or from said user, comprising means for generating a pseudo-random sequence specific to said user, means for determining, from a number of said pseudo-random sequence, a time at which a sequence is to be transmitted to or from said user, means for time-shifting the time at which the sequence is transmitted from an end of a preceding sequence by a time shift (θ m u), said time shift being determined as a function of a number of a pseudo-random sequence specific to said user; and means for transmitting said sequence to or from said user at the determined time.
- Claim: 14. A transmitter for transmitting data symbols to or from at least one user of an ultra bandwidth telecommunication system, each user (u) of said system being associated with a specific time hopping pattern consisting of a plurality (N s , N b) of integers (c j u), said transmitter comprising: a frame generator configured to generate a sequences of frames, each integer of said specific time hopping pattern being associated with a corresponding frame of said sequence; a pulse shifter configured to shift a pulse of said corresponding frame of said sequence by an amount of time (c j u T c) determined by said associated integer; and a pulse position modulator configured to modulate positions of pulses of a sequence by one or a plurality of data symbols to be transmitted to or from said user, comprising a pseudo-random sequence generator configured to for generate a pseudo-random sequence specific to said user, a transmission timer configured to determine, from a number of said pseudo-random sequence, a time at which a sequence is to be transmitted to or from said user, a time-shifter configured to shift the time at which the sequence is transmitted from an end of a preceding sequence by a time shift (θ m u), said time shift being determined as a function of a number of a pseudo-random sequence specific to said user; and a transmitter device configured to transmit said sequence to or from said user at the determined time.
- Claim: 15. In a method for transmitting data symbols to or from users of an ultra bandwidth telecommunication system, each user (u) of said system being associated with a specific time hopping pattern consisting of a plurality (N s , N b) of integers (c j u), a signal including said data symbols transmitted to or from a user consisting of sequences of frames, each integer of said specific time hopping pattern being associated with a corresponding frame and each frame containing a pulse time-shifted from the beginning thereof by an amount (c j u T c) determined by said associated integer, the pulses of one of said sequences being further position modulated by one or a plurality (n b) of said data symbols to be transmitted to or from said user, the improvement comprising: based on a pseudo-random sequence specific to said user, determining a time at which one of said sequences is to be transmitted to or from said user, and time-shifting the time at which the sequence is transmitted from an end of a preceding sequence by a time shift (θ m u), said time shift being determined as a function of a number of a pseudo-random sequence specific to said user.
- Current U.S. Class: 375/238
- Patent References Cited: 6226282 May 2001 Chung ; 2004/0057500 March 2004 Balachandran et al. ; WO 01/97396 December 2001
- Other References: Ramirez-Mireles F., XP001103037, “Performance of Ultrawideband SSMA Using Time Hopping and M-Ary PPM”; IEEE Journal on Selected Areas in Communication, IEEE Inc. New York, US, vol. 19, No. 6, Jun. 2001: pp. 1186-1196. cited by other ; Win M. Z. et al., XP000932191, “Ultra-Wide Bandwidth Time-Hopping Spead-Spectrum Impulse Radio for Wireless Multiple-Access Communicatiom”, IEEE Transactions on Communications, IEEE Inc. New York, US, vol. 48, No. 4, Apr. 2000, pp. 679-691. cited by other ; Tomaso Erseghe, et al.; “Ultra Wide Band Pulse Communications”; Thesis Study at the Universita Degli Studi Di Padova; pp. 1-144; Apr. 1999 to Dec. 2001. cited by other
- Primary Examiner: Kim, Kevin
- Attorney, Agent or Firm: Oblon, Spivak, McClelland, Maier & Neustadt, P.C.
|
