公开(公告)号：JPH11340847A

公开(公告)日：1999-12-10

申请号：JP11528799

申请日：1999-04-22

Applicant: LUCENT TECHNOLOGIES INC

Inventor： CHEN BRIAN ,  CARL-ERIK WILHELM

IPC: H04L27/00 ,  H04B1/04 ,  H04H20/00 ,  H04J11/00 ,  H04L5/02 ,  H04L27/36

Abstract: PROBLEM TO BE SOLVED: To reduce adjacent channel interference effectively in an adjacent area, in which an IBOC/CM system is used by making the power level of the sub-set of the digital modulation signal of the sub-band of a digital band lower than the power level of the second sub-set of the digital modulation signal of the second sub-band of the digital band. SOLUTION: An IBOC/AM system uses a digital band, using the analog host AM carrier wave with frequencies (fc) in 30 kHz width as a center. At the using of the IBOC/AM system in two adjacent regions to which the frequencies (fc) are assigned so as to be separated by 20 kHz, they mutually overlap by 10 kHz amount, and sub-adjacent channel interference is generated. In this case, a profile 301 is mounted in the region with the low frequencies (fc) among the two adjacent region mounts, and a profile 311 is mounted in the region with the high frequencies (fc). Thus, the profiles 301 and 311 do not overlap each other, and sub-adjacent channel interference can be prevented.

公开(公告)号：JP2000341247A

公开(公告)日：2000-12-08

申请号：JP2000089513

申请日：2000-03-28

Applicant: LUCENT TECHNOLOGIES INC

Inventor： MANSOUR DAVID ,  SINHA DEEPEN ,  CARL-ERIK WILHELM

IPC: H04L1/00 ,  H04B1/04 ,  H04H20/30 ,  H04H60/07 ,  H04J1/00 ,  H04J13/00 ,  H04L5/02

Abstract: PROBLEM TO BE SOLVED: To cope with contiguous channel interference in a contiguous area of an in-band on-channel system by transmitting multiple bit streams generated from an information signal according to multiple factors by using the frequency band of a host carrier signal. SOLUTION: An embedded audio encoder 203 is supplied with an analog audio signal a(t) and generates a C stream, an El stream, and an E2 stream representing analog signals on leads 209a, 209b, and 209c, The bit rates of the C stream, E1 stream, and E2 stream are M, S1, and S2 kb/sec respectively. For example, when the encoder 203 is a 48 kb/sec audio encoder, M, S1, and S2 can be 16, 16, and 16, respectively. The quality of the combination of the C stream, E1 stream, and E2 stream is much higher than the analog AM quality.