公开(公告)号：JPH1093516A

公开(公告)日：1998-04-10

申请号：JP22619897

申请日：1997-08-22

Applicant: LUCENT TECHNOLOGIES INC

Inventor： PAPADOPOULOS HARALABOS C ,  SUNDBERG CARL-ERIK WILHELM

IPC: H04J1/00 ,  H04H20/30 ,  H04J11/00

Abstract: PROBLEM TO BE SOLVED: To eliminate/reduce interference in the case of simultaneous transmis sion of an analog FM signal and a digital modulation signal. SOLUTION: A transmission system 300 is configured such that an analog FM signal denoting 1st information and a digital modulation signal denoting 2nd information are sent simultaneously on a same FM frequency band. Before the transmission, a multi-carrier modem 303 calculates the effect of the analog FM signal onto the digital modulation signal and a pre-processing unit 307 eliminates the effect in advance from an analog digital modulation signal. Moreover, a carrier subset used for actual digital transmission is selected by a carrier insert module 316 among digital transmission carriers of the multi-carrier modem 303 so that the interference onto the analog FM signal caused by digital transmission is at a minimum level. The corrected digital modulation signal and the analog FM signal are added and the sum is sent simultaneously at a composite signal.

公开(公告)号：JPH10163994A

公开(公告)日：1998-06-19

申请号：JP30318997

申请日：1997-11-05

Applicant: LUCENT TECHNOLOGIES INC

Inventor： PAPADOPOULOS HARALABOS C ,  SUNDBERG CARL-ERIK WILHELM

IPC: H03H21/00 ,  H03C3/00 ,  H04B1/66 ,  H04H20/30 ,  H04J1/00 ,  H04J1/12 ,  H04J9/00 ,  H04J11/00 ,  H04L27/10

Abstract: PROBLEM TO BE SOLVED: To provide a device and a method for generating digital modulated signals capable of being transmitted simultaneously with host analog FM signals and achieving wide coverage. SOLUTION: Synthetic signals x' (t) including the host analog FM signals and the digital modulated signals are transmitted by an allocated FM frequency band and then, the power spectrum of the digital modulated signals overlaps at least partially with the one of the analog FM signals. After receiving the synthetic signals, an extension Kalman filter 531 is used and the analog FM signals are generated corresponding at least to the synthetic signals. Information expressed by the digital modulation signals is reproduced as a difference between the synthetic signals and the analog FM signals.

公开(公告)号：CA2217429C

公开(公告)日：2001-04-17

申请号：CA2217429

申请日：1997-10-06

Applicant: LUCENT TECHNOLOGIES INC

Inventor： PAPADOPOULOS HARALABOS C ,  SUNDBERG CARL-ERIK WILHELM

IPC: H03H21/00 ,  H03C3/00 ,  H04B1/66 ,  H04H20/30 ,  H04J1/00 ,  H04J1/12 ,  H04J9/00 ,  H04J11/00 ,  H04L27/10 ,  H04L27/32 ,  H04B1/16

Abstract: In a system for simulcasting a digitally modulated signal and an analog FM signal over the same FM frequency band, the composite signal is received and applied to a conventional FM receiver, and a digital receiver in accordance with the invention. An extended Kalman filter is employed in the digital receiver to estimate the analog FM signal based on a version of the recovered FM signal from the FM receiver, and a discrete version of the composite signal whose spectrum has been translated and is at an intermediate carrier frequency. The estimated FM signal, which is in a discrete form, is subtracted from the discrete version of the composite signal. The resulting signal, which is an estimated version of the digitally modulated signal, is demodulated to recover the digital data as transmitted.

公开(公告)号：CA2217429A1

公开(公告)日：1998-05-12

申请号：CA2217429

申请日：1997-10-06

Applicant: LUCENT TECHNOLOGIES INC

Inventor： SUNDBERG CARL-ERIK WILHELM ,  PAPADOPOULOS HARALABOS C

IPC: H03H21/00 ,  H03C3/00 ,  H04B1/66 ,  H04H20/30 ,  H04J1/00 ,  H04J1/12 ,  H04J9/00 ,  H04J11/00 ,  H04L27/10 ,  H04L27/32 ,  H04B1/16

Abstract: In a system for simulcasting a digitally modulated signal and an analog FM signal over the same FM frequency band, the composite signal is received and applied to a conventional FM receiver, and a digital receiver in accordance with the invention. An extended Kalman filter is employed in the digital receiver to estimate the analog FM signal based on a version of the recovered FM signal from the FM receiver, and a discrete version of the composite signal whose spectrum has been translated and is at an intermediate carrier frequency. The estimated FM signal, which is in a discrete form, is subtracted from the discrete version of the composite signal. The resulting signal, which is an estimated version of the digitally modulated signal, is demodulated to recover the digital data as transmitted.

公开(公告)号：CA2321941A1

公开(公告)日：1998-02-22

申请号：CA2321941

申请日：1997-06-25

Applicant: LUCENT TECHNOLOGIES INC

Inventor： SUNDBERG CARL-ERIK WILHELM ,  PAPADOPOULOS HARALABOS C

IPC: H04L5/00 ,  H04L27/32

Abstract: The present invention relates to a method for use in a communications receiver. The method is comprised of receiving a data symbol corresponding to one of predetermined data symbols in a signal constellation. The method includes extending lines from an origin of the signal constellation through the predetermined data symbols therein, respectively and translating the received data symbol onto a selected one of the extended lines, the selected line being the closest to the received data symbol of all of the extended lines. Finally the method includes determining the predetermined data symbol corresponding to the translated received symbol. The invention also relates to a communications apparatus. The apparatus is comprised of a receiver for receiving a data symbol corresponding to one of predetermined data symbols in a signal constellation. A unit is provided for extending lines from an origin of the signal constellation through the predetermined data symbols therein, respectively, and a translator is provided for translating the received data symbol onto a selected one of the extended lines, the selected line being the closest to the received data symbol of all of the extended lines. A unit is provided for determining the predetermined data symbol corresponding to the translated received symbol.