Method and apparatus for a spectrally compliant cellular communication system

• US 20040043751A1
• Filed: 04/07/2003
• Published: 03/04/2004
• Est. Priority Date: 12/20/1999
• Status: Active Grant

• Current Assignee: IPR Licensing Incorporated (InterDigital, Inc.)
• Original Assignee: Tantivy Communications Incorporated (InterDigital, Inc.)
• Inventors: Amalfitano, Carlo, Proctor, James A Jr.
• Granted Patent: US 8,463,255 B2
• Time in Patent Office: Days
• US Class Current: 455/403
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04L 1/0042 Encoding specially adapted to other signal generation operation, e.g. in order to reduce transmit distortions, jitter, or to improve signal shape H04L1/0067 takes precedence
• CPC Class Codes: H04L 25/00 Baseband systems
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 36/185 using make before break
• CPC Class Codes: H04W 76/10 Connection setup

Abstract

A system for wireless data transmission that uses a channel bandwidth, channel separation, and radio frequency power spectrum which is compatible with existing deployments of wireless voice services. The transmitted waveforms are thus compatible with existing cellular networks. However, the time domain digital coding, modulation, and power control schemes are optimized for data transmission. Existing cellular network sites can thus be used to provide a high speed service optimized for wireless data traffic without the need for new radio frequency planning, and without interfering with existing voice service deployments.

Claims

1. A system for providing a data communication service over wireless radio links, the system dedicating at least one radio channel for data services only, and the dedicated channel not being used for providing a voice service, the system comprising:

a modulator, for modulating data to be transmitted over the dedicated channel, the modulator producing a modulated data signal having a bandwidth which is the same as modulated signal bandwidth of a voice signal modulated according to a digital wireless air interface standard for voice and data signal communication;

a radio frequency upconverter, for upconverting the modulated data signal to a radio carrier frequency such that a channel spacing between the modulated data signal and other radio signals in the system is compatible with a channel spacing specified by the digital wireless air interface standard; and

an encoder, for encoding the data prior to feeding the data to the modulator, the encoder being optimized for data services and using a different encoding scheme than an encoding scheme specified for voice and data signal communication by the digital wireless air interface standard.

2. A system as in claim 1 wherein the data service provided by the dedicated channel is IS-856.

3. A system as in claim 1 wherein the data service provided by the dedicated channel is T1.PP.723.

4. A system as in claim 1 wherein the data service provided by the dedicated channel is UMTS-FDD.

5. A system as in claim 1 wherein the data service provided by the dedicated channel is UMTS-TDD.

6. A system as in claim 1 wherein the data service provided by the dedicated channel uses orthogonal frequency division multiplexing (OFDM).

7. A system as in claim 1 wherein the digital air interface standard is IS-2000.

8. A system as in claim 1 wherein the digital air interface standard is CMDA-2000.

9. A system as in claim 1 wherein the modulator uses single carrier Time Division Duplex (TDD) to provide multiple slotted channels on a radio frequency carrier.

10. A system for providing a data communication service over wireless radio links, the system dedicating at least one radio channel for data services only, and the dedicated radio channel not being used for providing a voice service, the system comprising:

a radio frequency down converter, for down converting the modulated data signal from a radio carrier frequency;

a demodulator, for demodulating data transmitted over the dedicated radio channel, the demodulator producing demodulated data from a signal having a bandwidth which is the same as modulated signal bandwidth of a voice signal modulated according to a digital wireless air interface standard for voice signal communication;

a decoder, for decoding the data, the decoder being optimized for data services and using a different decoding scheme than a decoding scheme specified for voice signal communication by the digital wireless air interface standard.

11. A system as in claim 10 wherein the digital wireless air interface standard is provided for voice and data signal communication.

12. A system as in claim 10 additionally comprising:

a radio frequency down converter, for down converting the modulated voice signal from a radio carrier frequency specified by the digital wireless air interface standard;

a demodulator, for demodulating voice transmitted over the radio channel specified by the digital wireless air interface standard, the demodulator producing demodulated voice from a signal having a bandwidth which is the same as modulated signal bandwidth of the dedicated data signal.