WO1997050206A1 - Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel - Google Patents

Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel Download PDF

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Publication number
WO1997050206A1
WO1997050206A1 PCT/US1997/010760 US9710760W WO9750206A1 WO 1997050206 A1 WO1997050206 A1 WO 1997050206A1 US 9710760 W US9710760 W US 9710760W WO 9750206 A1 WO9750206 A1 WO 9750206A1
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WO
WIPO (PCT)
Prior art keywords
communication
data
rate
communication channel
channel
Prior art date
Application number
PCT/US1997/010760
Other languages
French (fr)
Inventor
Michael J. Luddy
Original Assignee
Interdigital Technology Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Interdigital Technology Corporation filed Critical Interdigital Technology Corporation
Priority to CA002259355A priority Critical patent/CA2259355C/en
Priority to DE69710892T priority patent/DE69710892T2/en
Priority to JP50339598A priority patent/JP3965494B2/en
Priority to DE0908036T priority patent/DE908036T1/en
Priority to AU34968/97A priority patent/AU3496897A/en
Priority to KR10-2004-7004090A priority patent/KR100500224B1/en
Priority to DK97931304T priority patent/DK0908036T3/en
Priority to EP97931304A priority patent/EP0908036B1/en
Priority to AT97931304T priority patent/ATE214220T1/en
Publication of WO1997050206A1 publication Critical patent/WO1997050206A1/en
Priority to HK99104357A priority patent/HK1019276A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H04B1/70751—Synchronisation aspects with code phase acquisition using partial detection
    • H04B1/70753—Partial phase search
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H04B1/70755—Setting of lock conditions, e.g. threshold
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H04B1/70758—Multimode search, i.e. using multiple search strategies
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7075—Synchronisation aspects with code phase acquisition
    • H04B1/708—Parallel implementation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/14—Two-way operation using the same type of signal, i.e. duplex
    • H04L5/1438—Negotiation of transmission parameters prior to communication
    • H04L5/1446—Negotiation of transmission parameters prior to communication of transmission speed
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/00912—Arrangements for controlling a still picture apparatus or components thereof not otherwise provided for
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N1/333—Mode signalling or mode changing; Handshaking therefor
    • H04N1/3333—Mode signalling or mode changing; Handshaking therefor during transmission, input or output of the picture signal; within a single document or page
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
    • H04W28/18—Negotiating wireless communication parameters
    • H04W28/20—Negotiating bandwidth
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/542—Allocation or scheduling criteria for wireless resources based on quality criteria using measured or perceived quality
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2201/00—Indexing scheme relating to details of transmission systems not covered by a single group of H04B3/00 - H04B13/00
    • H04B2201/69—Orthogonal indexing scheme relating to spread spectrum techniques in general
    • H04B2201/707—Orthogonal indexing scheme relating to spread spectrum techniques in general relating to direct sequence modulation
    • H04B2201/70702—Intercell-related aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2201/00—Indexing scheme relating to details of transmission systems not covered by a single group of H04B3/00 - H04B13/00
    • H04B2201/69—Orthogonal indexing scheme relating to spread spectrum techniques in general
    • H04B2201/707—Orthogonal indexing scheme relating to spread spectrum techniques in general relating to direct sequence modulation
    • H04B2201/70703—Orthogonal indexing scheme relating to spread spectrum techniques in general relating to direct sequence modulation using multiple or variable rates
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N2201/00—Indexing scheme relating to scanning, transmission or reproduction of documents or the like, and to details thereof
    • H04N2201/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N2201/333—Mode signalling or mode changing; Handshaking therefor
    • H04N2201/33307—Mode signalling or mode changing; Handshaking therefor of a particular mode
    • H04N2201/33342—Mode signalling or mode changing; Handshaking therefor of a particular mode of transmission mode
    • H04N2201/3335—Speed or rate
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/543—Allocation or scheduling criteria for wireless resources based on quality criteria based on requested quality, e.g. QoS
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/12—Access point controller devices

Definitions

  • This invention generally relates to wireless communication systems. More particularly, the invention relates to a wireless digital CDMA communication system that selectively adjusts the data transmission rate depending upon the bandwidth required by the communication without the loss of data during the transmission rate adjustment.
  • One of the problems associated with wireless communication of data is that many different types of communicating nodes are currently in use including computers, facsimile machines, automatic calling and answering equipment and other types of data networks. These nodes may be able to communicate at a plurality of different data rates and must be properly synchronized to avoid losing data during the establishment or maintenance of a communication.
  • the present invention is a CDMA communication system which prevents the transmission of data between communicating nodes until the data communication rate required by the communicating nodes has been completely established throughout the system.
  • the system selectively suppresses the confirmation tone that a receiving node sends to an originating node. Accordingly, the transmission of voice, facsimile or modem data is prevented until the communication path has been established at the desired communication rate.
  • This permits the system to reliably transport encoded data at a plurality of data rates across a telecommunication system which may lack precise synchronization. Accordingly, it is an object of the present invention to provide a system and method for reliably transmitting encoded data by preventing communication of data until the communication system has achieved the data transmission rate required by communicating nodes.
  • Figure 1 is a schematic overview of a code division multiple access communication system in accordance with the present invention
  • Figure 2 is a block diagram of the communication system of Figure 1 connected to originating and terminating nodes;
  • Figure 3 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the prior art;
  • Figure 4 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the present invention.
  • FIG. 5 is a block diagram of a base station in accordance with the teachings of the present invention.
  • a communication network 10 embodying the present invention is shown in Figure 1.
  • the communication network 10 generally comprises one or more base stations 14, each of which is in wireless communication with a plurality of subscriber units 16, which may be fixed or mobile. Each subscriber unit 16 communicates with either the closest base station 14 or the base station 14 which provides the strongest communication signal.
  • the base stations 14 also communicate with a base station controller 20 which coordinates communications among the base stations 14.
  • the communication network 10 may also be connected to a public switched telephone network (PSTN) 22, wherein the base station controller 20 also coordinates communications between the base stations 14 and the PSTN 22.
  • PSTN public switched telephone network
  • each base station 14 communicates with the base station controller 20 over a wireless link.
  • the link between the base stations 14 and the base station controller 20 is shown as a wireless link, it should be apparent to those skilled in the art that a land line between the base stations 14 and the base station controller 20 may be provided. This is particularly applicable when a base station 14 is in close proximity to the base station controller 20.
  • the base station controller 20 performs several functions. Primarily, the base station controller 20 provides all of the overhead, administrative and maintenance (OA&M) signaling associated with establishing and maintaining all of wireless communications between the subscriber units 16, the base stations 14, and the base station controller 20.
  • the base station controller 20 also provides an interface between the wireless communication system 10 and the PSTN 22. This interface includes multiplexing and demultiplexing of a plurality of communication signals that enter and leave the system 10 via the base station controller 20.
  • the wireless communication system 10 is shown employing antennas to transmit RF signals, one skilled in the art should recognize that communications may be accomplished by microwave satellite uplinks.
  • the communication system 10 is generally connected to originating nodes 40 and terminating nodes 44.
  • the communication system 10 selectively allots the bandwidth required for supporting the data transmission rate required by the originating and terminating nodes 40, 44. In this manner, the system 10 ensures that the bandwidth is utilized efficiently.
  • Voiced communications may be effectively transmitted across a 32 Kbs adaptive pulse code modulation (ADPCM) channel.
  • ADPCM adaptive pulse code modulation
  • PCM pulse code modulation
  • Many other types of modulation techniques and data transmission rates may also be utilized by originating and terminating nodes 40, 44.
  • the system 10 must be able to effectively allocate bandwidth and dynamically switch between these data communication rates and modulation schemes on demand.
  • the communication system 10 provides a communication link between the originating and terminating nodes 40, 44.
  • the originating and terminating nodes 40, 44 may comprise computers, facsimile machines, automatic calling and answering equipment, data networks or any combination of this equipment. For robust communication of data it is imperative to ensure that the communication system 10 switches to the data transmission rate required by the communicating nodes 40, 44 prior to the transmission of any data.
  • the originating node 40 periodically transmits a calling tone (step 100) which indicates that a data communication, (not a voice communication) , is to be transmitted.
  • the calling tone which is sent from the originating node 40 to the terminating node 44 is detected by the terminating node 44 (step 102) which initiates several actions.
  • the terminating node 44 prepares to send a data communication (step 104) .
  • the terminating node 44 transmits an answering tone (step 106) to the originating node 40 to confirm that the terminating node 44 has received the calling tone.
  • the originating node 40 Upon receipt of the answering tone (step 108) , the originating node 40 begins the transmission of data (step 110) , which is received by the terminating node 44 (step 112) . With the communication link established at the data transmission rate, the originating and terminating 40, 44 nodes transmit and receive data until termination of the communication.
  • the transmission rate of the communication system 10 is transparent to both the communicating and terminating nodes 40, 44. Modification of the transmission rate from a low rate (that supports voice communication) to a high rate (that supports encoded data communication) ensures that data will be reliably and quickly transmitted over a communication channel. However, the new transmission rate must be completely established throughout the communication system 10 to prevent false interpretation of tones transmitted by the originating node 40.
  • the originating node 40 may begin transmission of data at a high rate before the system 10 has fully switched from 32 Kbs ADPCM to 64 Kbs PCM resulting in loss of data.
  • the present invention blocks the transmission of the confirming tone to the originating node 40 until the new data transmission rate has been completely established throughout the communication system 10. This prevents the reception of the answering tone at the transmitting node 40 and ensures the reliable transportation of encoded data at a higher rate across a communication system 10 which lacks the precise synchronization which would otherwise be required.
  • the operation of the system 10 of the present invention will be explained with reference to Figure 4.
  • the communication system 10 facilitates communications between an originating node 40 and a terminating node 44.
  • the actions of the originating node 40 (steps 202, 212 and 214) and the actions of the terminating node 44 (steps 206, 207, 208 and 218) are the same as in Figure 3.
  • the operation of the communication system 10 is transparent to both the originating node 40 and the terminating node 44.
  • the originating node 40 periodically transmits a calling tone (step 202) which indicates a data communication.
  • the communication system 10 performs several actions in response to receipt of the calling tone (step 204) .
  • the calling tone is received at 32 Kbs ADPCM which is the standard communication setting for voice communications.
  • the system 10 detects the calling tone and initiates a switch to 64 Kbs PCM in order to handle the high-speed data transmission. This switch must be implemented by the base station 14, the subscriber unit 16 and the base station controller 20. Although the system 10 immediately begins the switching over to the new data transmission rate, the process takes approximately 1500 msec to implement. Accordingly, the system 10 transmits the calling tone to the terminating node 44 at 32 Kbs ADPCM.
  • the terminating node 44 detects the calling tone (step 206) and prepares to send a data communication (step 207) .
  • the terminating node 44 subsequently transmits the answering tone (step 208) which, when received by the originating node, will cause the originating node 40 to begin transmission of data.
  • the communication system 10 receives the answering tone from the terminating node 44. However, the system 10 does not forward the answering tone to the originating node 40 until the switch to 64 Kbs PCM has been established throughout the system 10. After the system 10 has confirmed that the switch to 64 Kbs PCM has been achieved, it permits the answering tone to pass through to the originating node 40, which receives the tone (step 212) . In response to the answering tone, the originating node 40 begins transmission of data (step 214) . The system 10 receives the data and begins transmission of data at the new data transmission rate (64 Kbs PCM) (step 216) to the terminating node 44 which receives the data (step 218) . Since the communication channel has been established, the originating and terminating nodes 40, 44 continue to communicate over the system 10 in this manner (steps 214, 216 and 218) until the communication is terminated.
  • the base station controller 20 controls at least a portion of the communication link between two communicating nodes 40, 44.
  • This link comprises the transmission path 300 from a first communicating node to the base station controller 20, the transmission path 302 within the base station controller 20, and the transmission path 304 from the base station controller 20 to the second communicating node.
  • the transmission paths 300, 304 to and from the base station controller 20 may include a plurality of base stations 14 and subscriber units 16 which are controlled by the base station controller 20.
  • the communications between an originating node 40 and a terminating node 44 are transmitted over a virtual channel as is well known by those of skill in the art . Since the entire spectrum is used by the CDMA communication system 10, communications from the originating node 40 to the terminating node 44 are transmitted over the same frequency band as communications from the terminating node 44 to the originating node 40. After the virtual channel has been established, the originating and terminating nodes 40, 44 may freely communicate.
  • the base station controller 20 includes a calling tone detector 310, a microprocessor 312 and an answering tone blocker 314.
  • the calling tone detector 310 monitors the communication channel which has been established in order to detect the calling tone.
  • the calling tone detector 310 detects the calling tone, which causes the base station controller 20 to initiate the switch to a higher data transmission rate.
  • the microprocessor 312 subsequently informs any other base stations 14 or subscriber units 16 through which the communication is to be routed (hereinafter called communicating equipment) to initiate the switch to the higher data transmission rate.
  • the microprocessor 312 activates the answering tone blocker 314 which will prevent the answering tone from being transmitted through the system 10.
  • Each piece of communicating equipment 14, 16, 20 transmits an acknowledgment to the microprocessor 312 of the base station controller 20 when the higher data transmission rate has been achieved.
  • the microprocessor 312 subsequently deactivates the answering tone blocker 314 which permits the answering tone to be forwarded to the originating node 40.
  • the communicating nodes 40, 44 commence data transmission over the communication system 10 at the higher data transmission rate .
  • the functions performed by the base station controller 20 shown in Figure 5 may, in an alternative embodiment, be performed by a base station 14 coupled with either the originating or terminating nodes 40.
  • the functions of a base station 14 may also be combined with the base station controller 20, to form a master base station.
  • different data rates and modulation schemes may be employed. It will be appreciated by those skilled in the art that many variations may be made in the structure and mode of operation without departing from the spirit and scope of the invention as disclosed in the teachings herein.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Quality & Reliability (AREA)
  • Multimedia (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Communication Control (AREA)
  • Radio Relay Systems (AREA)
  • Time-Division Multiplex Systems (AREA)

Abstract

A CDMA communication system which prevents the transmission of data between communicating nodes until the data communication rate required by the communicating nodes has been completely established throughout the system selectively suppresses (314) the confirmation tone that a receiving node sends to an originating node. The transmission of voice, facsimile or modem data is prevented until the communication path has been established at the desired communication rate. This permits the system to reliably transport encoded data at a plurality of data rates across a telecommunication system which may lack precise synchronization.

Description

CDMA COMMUNICATION SYSTEM WHICH SELECTIVELY SUPPRESSES DATA TRANSMISSIONS DURING ESTABLISHMENT OF A COMMUNICATION CHANNEL
BACKGROUND OF THE INVENTION Field of the Invention
This invention generally relates to wireless communication systems. More particularly, the invention relates to a wireless digital CDMA communication system that selectively adjusts the data transmission rate depending upon the bandwidth required by the communication without the loss of data during the transmission rate adjustment.
Description of Related Art
The telecommunications industry has recently experienced strong growth in the use of wireless technology including cellular, satellite and microwave communications. As the popularity and use of wireless communication systems has increased, the finite bandwidth allocated to each type of wireless communication has become increasingly valuable. Since it is unlikely that additional bandwidth to support user growth will be allocated for existing applications, many of the recent advances in telecommunication hardware and software have been directed toward increasing the transmission rate of data while utilizing the same or a decreased bandwidth.
One of the problems associated with wireless communication of data is that many different types of communicating nodes are currently in use including computers, facsimile machines, automatic calling and answering equipment and other types of data networks. These nodes may be able to communicate at a plurality of different data rates and must be properly synchronized to avoid losing data during the establishment or maintenance of a communication.
The establishment and synchronization of communications is currently performed using a variety of different techniques. For example, the system disclosed in U.S. Patent No. 4,384,307 (Kuzmik et al . ) includes a communication adapter for interfacing a transceiver to a communication line. The system requires bit level manipulation of data to properly synchronize two communicating nodes. Reformatting of data using this technique is computationally expensive and prone to errors.
Another type of system is disclosed in U.S. Patent No. 4,583,124 (Tsuji et al. ) which permits two nodes to quickly establish synchronization at a desired communication speed by storing information concerning each communicating node in memory. However, requiring an originating node to store information about each receiving node is impractical given today's communication environment.
Accordingly, there is a need for a simple and effective technique for switching the data transmission rate of a communication network to the required rate while preserving the integrity of the data transmitted between two communicating nodes.
SUMMARY OF THE INVENTION The present invention is a CDMA communication system which prevents the transmission of data between communicating nodes until the data communication rate required by the communicating nodes has been completely established throughout the system. The system selectively suppresses the confirmation tone that a receiving node sends to an originating node. Accordingly, the transmission of voice, facsimile or modem data is prevented until the communication path has been established at the desired communication rate. This permits the system to reliably transport encoded data at a plurality of data rates across a telecommunication system which may lack precise synchronization. Accordingly, it is an object of the present invention to provide a system and method for reliably transmitting encoded data by preventing communication of data until the communication system has achieved the data transmission rate required by communicating nodes. Other objects and advantages of the present invention will become apparent after reading the description of a presently preferred embodiment .
BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a schematic overview of a code division multiple access communication system in accordance with the present invention;
Figure 2 is a block diagram of the communication system of Figure 1 connected to originating and terminating nodes; Figure 3 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the prior art; Figure 4 is a flow diagram of the establishment of a communication channel between originating and terminating nodes in accordance with the present invention; and
Figure 5 is a block diagram of a base station in accordance with the teachings of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment will be described with reference to the drawing figures where identical numerals represent similar elements throughout. A communication network 10 embodying the present invention is shown in Figure 1. The communication network 10 generally comprises one or more base stations 14, each of which is in wireless communication with a plurality of subscriber units 16, which may be fixed or mobile. Each subscriber unit 16 communicates with either the closest base station 14 or the base station 14 which provides the strongest communication signal. The base stations 14 also communicate with a base station controller 20 which coordinates communications among the base stations 14. The communication network 10 may also be connected to a public switched telephone network (PSTN) 22, wherein the base station controller 20 also coordinates communications between the base stations 14 and the PSTN 22. Preferably, each base station 14 communicates with the base station controller 20 over a wireless link. Although the link between the base stations 14 and the base station controller 20 is shown as a wireless link, it should be apparent to those skilled in the art that a land line between the base stations 14 and the base station controller 20 may be provided. This is particularly applicable when a base station 14 is in close proximity to the base station controller 20. The base station controller 20 performs several functions. Primarily, the base station controller 20 provides all of the overhead, administrative and maintenance (OA&M) signaling associated with establishing and maintaining all of wireless communications between the subscriber units 16, the base stations 14, and the base station controller 20. The base station controller 20 also provides an interface between the wireless communication system 10 and the PSTN 22. This interface includes multiplexing and demultiplexing of a plurality of communication signals that enter and leave the system 10 via the base station controller 20. Although the wireless communication system 10 is shown employing antennas to transmit RF signals, one skilled in the art should recognize that communications may be accomplished by microwave satellite uplinks. Referring to Figure 2, the communication system 10 is generally connected to originating nodes 40 and terminating nodes 44. In order to conserve as much bandwidth as possible, the communication system 10 selectively allots the bandwidth required for supporting the data transmission rate required by the originating and terminating nodes 40, 44. In this manner, the system 10 ensures that the bandwidth is utilized efficiently. Voiced communications may be effectively transmitted across a 32 Kbs adaptive pulse code modulation (ADPCM) channel. However, a high speed fax or data modem signal requires at least a 64 Kbs pulse code modulation (PCM) signal to reliably transmit the communication. Many other types of modulation techniques and data transmission rates may also be utilized by originating and terminating nodes 40, 44. The system 10 must be able to effectively allocate bandwidth and dynamically switch between these data communication rates and modulation schemes on demand.
The communication system 10 provides a communication link between the originating and terminating nodes 40, 44. The originating and terminating nodes 40, 44 may comprise computers, facsimile machines, automatic calling and answering equipment, data networks or any combination of this equipment. For robust communication of data it is imperative to ensure that the communication system 10 switches to the data transmission rate required by the communicating nodes 40, 44 prior to the transmission of any data.
Referring to Figure 3, the typical procedure for establishing communications between originating nodes 40 and terminating nodes is shown. The originating node 40 periodically transmits a calling tone (step 100) which indicates that a data communication, (not a voice communication) , is to be transmitted. The calling tone which is sent from the originating node 40 to the terminating node 44 is detected by the terminating node 44 (step 102) which initiates several actions. First, the terminating node 44 prepares to send a data communication (step 104) . Next, the terminating node 44 transmits an answering tone (step 106) to the originating node 40 to confirm that the terminating node 44 has received the calling tone. Upon receipt of the answering tone (step 108) , the originating node 40 begins the transmission of data (step 110) , which is received by the terminating node 44 (step 112) . With the communication link established at the data transmission rate, the originating and terminating 40, 44 nodes transmit and receive data until termination of the communication.
One problem with this process is that the transmission rate of the communication system 10 is transparent to both the communicating and terminating nodes 40, 44. Modification of the transmission rate from a low rate (that supports voice communication) to a high rate (that supports encoded data communication) ensures that data will be reliably and quickly transmitted over a communication channel. However, the new transmission rate must be completely established throughout the communication system 10 to prevent false interpretation of tones transmitted by the originating node 40. The originating node 40 may begin transmission of data at a high rate before the system 10 has fully switched from 32 Kbs ADPCM to 64 Kbs PCM resulting in loss of data.
In order to obviate tone misinterpretation and to prevent the resulting erroneous operation of the originating or transmitting nodes 40, 44, the present invention blocks the transmission of the confirming tone to the originating node 40 until the new data transmission rate has been completely established throughout the communication system 10. This prevents the reception of the answering tone at the transmitting node 40 and ensures the reliable transportation of encoded data at a higher rate across a communication system 10 which lacks the precise synchronization which would otherwise be required. The operation of the system 10 of the present invention will be explained with reference to Figure 4. The communication system 10 facilitates communications between an originating node 40 and a terminating node 44. As shown, the actions of the originating node 40 (steps 202, 212 and 214) and the actions of the terminating node 44 (steps 206, 207, 208 and 218) are the same as in Figure 3. The operation of the communication system 10 is transparent to both the originating node 40 and the terminating node 44.
In operation, the originating node 40 periodically transmits a calling tone (step 202) which indicates a data communication. The communication system 10 performs several actions in response to receipt of the calling tone (step 204) . First, the calling tone is received at 32 Kbs ADPCM which is the standard communication setting for voice communications. The system 10 detects the calling tone and initiates a switch to 64 Kbs PCM in order to handle the high-speed data transmission. This switch must be implemented by the base station 14, the subscriber unit 16 and the base station controller 20. Although the system 10 immediately begins the switching over to the new data transmission rate, the process takes approximately 1500 msec to implement. Accordingly, the system 10 transmits the calling tone to the terminating node 44 at 32 Kbs ADPCM. The terminating node 44 detects the calling tone (step 206) and prepares to send a data communication (step 207) . The terminating node 44 subsequently transmits the answering tone (step 208) which, when received by the originating node, will cause the originating node 40 to begin transmission of data.
The communication system 10 receives the answering tone from the terminating node 44. However, the system 10 does not forward the answering tone to the originating node 40 until the switch to 64 Kbs PCM has been established throughout the system 10. After the system 10 has confirmed that the switch to 64 Kbs PCM has been achieved, it permits the answering tone to pass through to the originating node 40, which receives the tone (step 212) . In response to the answering tone, the originating node 40 begins transmission of data (step 214) . The system 10 receives the data and begins transmission of data at the new data transmission rate (64 Kbs PCM) (step 216) to the terminating node 44 which receives the data (step 218) . Since the communication channel has been established, the originating and terminating nodes 40, 44 continue to communicate over the system 10 in this manner (steps 214, 216 and 218) until the communication is terminated.
Referring to Figure 5, a more detailed block diagram of the base station controller 20 is shown. The base station controller 20 controls at least a portion of the communication link between two communicating nodes 40, 44. This link comprises the transmission path 300 from a first communicating node to the base station controller 20, the transmission path 302 within the base station controller 20, and the transmission path 304 from the base station controller 20 to the second communicating node. The transmission paths 300, 304 to and from the base station controller 20 may include a plurality of base stations 14 and subscriber units 16 which are controlled by the base station controller 20.
It should be appreciated by those of skill in the art that the establishment of a communication channel between communicating nodes 40, 44 is a complex procedure involving a plurality of tasks performed by the base station 14, the subscriber unit 16 and the base station controller 20. A detailed description of the entire procedure is outside the scope of the present invention. Accordingly, only those portions of the procedure for establishment of a communication channel relevant to the present invention will be described hereinafter.
The communications between an originating node 40 and a terminating node 44 are transmitted over a virtual channel as is well known by those of skill in the art . Since the entire spectrum is used by the CDMA communication system 10, communications from the originating node 40 to the terminating node 44 are transmitted over the same frequency band as communications from the terminating node 44 to the originating node 40. After the virtual channel has been established, the originating and terminating nodes 40, 44 may freely communicate.
The base station controller 20 includes a calling tone detector 310, a microprocessor 312 and an answering tone blocker 314. The calling tone detector 310 monitors the communication channel which has been established in order to detect the calling tone. When a calling tone is transmitted from an originating node 40, the calling tone detector 310 detects the calling tone, which causes the base station controller 20 to initiate the switch to a higher data transmission rate. The microprocessor 312 subsequently informs any other base stations 14 or subscriber units 16 through which the communication is to be routed (hereinafter called communicating equipment) to initiate the switch to the higher data transmission rate.
The microprocessor 312 activates the answering tone blocker 314 which will prevent the answering tone from being transmitted through the system 10. Each piece of communicating equipment 14, 16, 20 transmits an acknowledgment to the microprocessor 312 of the base station controller 20 when the higher data transmission rate has been achieved. The microprocessor 312 subsequently deactivates the answering tone blocker 314 which permits the answering tone to be forwarded to the originating node 40. The communicating nodes 40, 44 commence data transmission over the communication system 10 at the higher data transmission rate .
Although the invention has been described in part by making detailed reference to the preferred embodiment, such detail is intended to be instructive rather than restrictive. For example, the functions performed by the base station controller 20 shown in Figure 5 may, in an alternative embodiment, be performed by a base station 14 coupled with either the originating or terminating nodes 40. The functions of a base station 14 may also be combined with the base station controller 20, to form a master base station. Additionally, different data rates and modulation schemes may be employed. It will be appreciated by those skilled in the art that many variations may be made in the structure and mode of operation without departing from the spirit and scope of the invention as disclosed in the teachings herein.

Claims

What is claimed is:
1. A system for suppressing selective communications during bearer rate modification in a communication network, the system comprising: means for establishing a communication channel between first and second communicating nodes at a first data rate; means for detecting a transmission from said first node on said channel; means for determining whether said transmission requires a change in data rates to a second data rate; switch means, responsive to said determining means, for switching said communication channel to said second data rate; and blocking means, responsive to said determining means, for blocking transmissions from said second node until said second data rate has been established.
2. The system of claim 1 wherein said detecting means detects tones at a plurality of selective frequencies and said tones initiate a change to said second data rate.
3. The system of claim 2 wherein said switch means switches said first data rate to said second, higher data rate.
4. The system of claim 3 wherein said first data rate is 32 kb/s and said second data rate is 64 kb/s.
5. The system of claim 4 wherein said first data rate employs pulse code modulation and said second data rate employs adaptive pulse code modulation.
6. The system of claim 1 wherein said switch means is responsive to said determining means to switch said established channel to one of a plurality of alternative channels, depending upon the required data rate and modulation type.
7. A communication system for selectively adjusting data transmission rates without the loss of data during the transmission rate adjustment, the system comprising: means for establishing a communication channel between an originating node and a terminating node, said channel comprising a first communication path from said originating node to said terminating node and a second communication path from said terminating node to said originating node; means for monitoring said first communication path for a signal, said signal indicating the request for a transmission rate adjustment; adjustment means, responsive to said detection means, for adjusting the transmission rate of said communication channel; and suppression means, responsive to said detection means, for suppressing communications on said second communication path until the desired communication rate is established.
8. The system of claim 7 wherein said monitoring means detects signals having selective frequencies indicating a request for an increased data transmission rate.
9. The system of claim 8 wherein said adjustment means switches said communication channel to a second communication channel having said higher data transmission rate.
10. The system of claim 9 wherein said communication channel has a data rate of 32 kb/s and said second communication channel has a data rate of 64 kb/s.
11. The system of claim 10 wherein said communication channel uses pulse code modulation and said second communication channel uses adaptive pulse code modulation.
12. The system of claim 11 wherein said signal indicates the data rate and modulation type required and said adjustment means is responsive to said monitoring means to switch said channel to one of a plurality of alternative channels, depending upon the required data rate and modulation.
13. A method for modifying the data transmission rate of a communication system comprising: receiving a first communication from an originating node at a first data communication rate; detecting a request for a modification of said data communication rate; initiating a modification to said requested data communication rate; transmitting said first communication at said first data rate to a terminating node; receiving a second communication from said terminating node; suppressing said answering tone until said modification is completed; completing said modification; and transmitting said second communication to said originating node.
14. A system for suppressing selective communications during channel modification in a communication network, the system comprising: means for establishing a first duplex communication channel between first and second communicating nodes comprising a transmit (Tx) portion and a receive (Rx) portion; said channel having a first data communication rate and modulation type; means for detecting a transmission from said first node on said Tx portion; means for determining whether said transmission requires a change to a second duplex communication channel having a second data communication rate and modulation type; switch means, responsive to said determining means, for switching said first communication channel to said second communication channel; and blocking means, responsive to said determining means, for blocking transmissions on said Rx portion until said second communication channel is established.
15. The system of claim 1 wherein said detecting means detects selective transmitted frequencies on said Tx portion which indicate a requirement for a change to said second communication channel.
16. The system of claim 2 wherein said second communication channel has a faster data rate than said first communication rate .
17. The system of claim 3 wherein said first data communication rate is 32 kb/s and said second data communication rate is 64 kb/s.
18. The system of claim 4 wherein said first data communication channel uses pulse code modulation and said second communication channel uses adaptive pulse code modulation.
19. The system of claim 1 wherein said switch means is responsive to said determining means to switch said established channel to one of a plurality of alternative channels, depending upon the requested data rate and modulation.
20. A system for suppressing selective communications during bearer rate modification in a communication network, the system comprising: means for establishing a communication channel between first and second communicating entities; means for detecting a transmission from said first entity over said channel; determining means responsive to said detecting means, determining if a new communication channel is required; switch means, responsive to said determining means, for switching over said communication channel to a communication channel; blocking means, responsive to said determining means, for blocking transmissions from said second entity to said first entity until said switch over is completed.
21. A method for modifying the data transmission rate of a communication system comprising: receiving a first communication from an originating node at a first data communication rate; detecting the data rate and type of modulation required to support said first communication; initiating a modification to a second communication channel having said data rate and type of modulation; transmitting said first communication at said first data rate to a terminating node; receiving a second communication from said terminating node; suppressing said second communication until said modification is completed; and transmitting said second communication to said originating node.
PCT/US1997/010760 1996-06-27 1997-06-20 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel WO1997050206A1 (en)

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CA002259355A CA2259355C (en) 1996-06-27 1997-06-20 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel
DE69710892T DE69710892T2 (en) 1996-06-27 1997-06-20 DATA TRANSMISSIONS DURING THE COMMUNICATION CHANNEL STRUCTURE, SELECTIVELY PREVENTING CDMA COMMUNICATION SYSTEM
JP50339598A JP3965494B2 (en) 1996-06-27 1997-06-20 CDMA communication system for selectively inhibiting data transmission during communication channel setting period
DE0908036T DE908036T1 (en) 1996-06-27 1997-06-20 DATA TRANSMISSIONS DURING THE COMMUNICATION CHANNEL STRUCTURE, SELECTIVELY PREVENTING CDMA COMMUNICATION SYSTEM
AU34968/97A AU3496897A (en) 1996-06-27 1997-06-20 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel
KR10-2004-7004090A KR100500224B1 (en) 1996-06-27 1997-06-20 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel
DK97931304T DK0908036T3 (en) 1996-06-27 1997-06-20 CDMA communication system which selectively suppresses data transmissions during the establishment of a communication channel
EP97931304A EP0908036B1 (en) 1996-06-27 1997-06-20 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel
AT97931304T ATE214220T1 (en) 1996-06-27 1997-06-20 DATA TRANSFERS DURING COMMUNICATION CHANNEL SETUP SELECTIVELY PREVENTING CDMA COMMUNICATIONS SYSTEM
HK99104357A HK1019276A1 (en) 1996-06-27 1999-10-06 Cdma communication system which selectively suppresses data transmissions during establishment of a communication channel

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SG108240A1 (en) * 2000-02-23 2005-01-28 Ntt Docomo Inc Multi-carrier cdma radio transmitting method and apparatus, and channel estimation method and apparatus for multi-carrier cdma radio transmitting system
US9525455B2 (en) 2002-04-29 2016-12-20 Interdigital Technology Corporation Simple and robust digital code tracking loop for wireless communication systems

Families Citing this family (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6816473B2 (en) 1995-06-30 2004-11-09 Interdigital Technology Corporation Method for adaptive forward power control for spread-spectrum communications
ZA965340B (en) 1995-06-30 1997-01-27 Interdigital Tech Corp Code division multiple access (cdma) communication system
US6697350B2 (en) 1995-06-30 2004-02-24 Interdigital Technology Corporation Adaptive vector correlator for spread-spectrum communications
US7020111B2 (en) * 1996-06-27 2006-03-28 Interdigital Technology Corporation System for using rapid acquisition spreading codes for spread-spectrum communications
US6885652B1 (en) 1995-06-30 2005-04-26 Interdigital Technology Corporation Code division multiple access (CDMA) communication system
US5953346A (en) * 1996-06-27 1999-09-14 Interdigital Technology Corporation CDMA communication system which selectively suppresses data transmissions during establishment of a communication channel
US7929498B2 (en) 1995-06-30 2011-04-19 Interdigital Technology Corporation Adaptive forward power control and adaptive reverse power control for spread-spectrum communications
US6873597B1 (en) * 1999-08-11 2005-03-29 Nortel Networks Limited Reduced data rate communication system
FI19992166A (en) * 1999-10-08 2001-04-09 Nokia Networks Oy Method of changing the route of a data transmission and increasing the number of connections through a data transmission link
US7006494B1 (en) 2000-01-04 2006-02-28 Cisco Technology, Inc. System and method for a virtual telephony intermediary
US7079495B1 (en) 2000-01-04 2006-07-18 Cisco Technology, Inc. System and method for enabling multicast telecommunications
US6804254B1 (en) * 2000-01-04 2004-10-12 Cisco Technology, Inc. System and method for maintaining a communication link
US7069432B1 (en) * 2000-01-04 2006-06-27 Cisco Technology, Inc. System and method for providing security in a telecommunication network
US6697618B1 (en) * 2000-04-19 2004-02-24 Phonex Broadband Corporation System and method for detecting failures in a wireless phone/modem jack to prevent telephone line seizures
US8321542B1 (en) 2000-05-05 2012-11-27 Ipr Licensing, Inc. Wireless channel allocation in a base station processor
JP2001320438A (en) * 2000-05-12 2001-11-16 Nec Corp Communication system
US8301137B1 (en) 2000-07-31 2012-10-30 Interdigital Patent Corporation Method and apparatus for wireless router multicast
GB0024694D0 (en) * 2000-10-09 2000-11-22 Nokia Networks Oy Connection set-up in a communication system
EP1278341B1 (en) * 2001-01-26 2005-04-13 Nec Corporation Method and system for controlling a communication network and a router used in the network
US20020186833A1 (en) * 2001-03-29 2002-12-12 Lucas Phillip W. System and method of communicating via an in-band tone messaging protocol
US6980560B2 (en) * 2001-05-25 2005-12-27 Mindspeed Technologies, Inc. System and method for connecting communication devices over packet networks
US6985481B2 (en) * 2001-05-25 2006-01-10 Mindspeed Technologies, Inc. System and method for handling V.8bis signals for modem connections over packet networks
EP1271855A1 (en) * 2001-06-29 2003-01-02 BRITISH TELECOMMUNICATIONS public limited company Method and apparatus for routing data
EP1400072A1 (en) * 2001-06-29 2004-03-24 British Telecommunications Public Limited Company Method and apparatus for routing data with support for changing mobility requirements
WO2003047281A1 (en) 2001-11-26 2003-06-05 Nokia Corporation Mac layer inverse multiplexing in a third generation ran
JP3927027B2 (en) * 2001-12-21 2007-06-06 株式会社エヌ・ティ・ティ・ドコモ Resource control system, resource control method, and base station suitable for use in the same
JP2005311614A (en) * 2004-04-20 2005-11-04 Pioneer Electronic Corp Information distribution system, method and program and information recording medium
US7177030B2 (en) * 2004-04-22 2007-02-13 Technion Research And Development Foundation Ltd. Determination of thin film topography
US8825098B2 (en) * 2005-04-01 2014-09-02 Interdigital Technology Corporation Method and apparatus for providing multi-rate broadcast services
US8203983B2 (en) * 2007-03-15 2012-06-19 Lantiq Deutschland Gmbh Multi-domain network with centralized management
US8036702B2 (en) * 2007-05-14 2011-10-11 Intel Corporation Method and apparatus for multicarrier communication in wireless systems
CN102012827A (en) * 2010-11-22 2011-04-13 中兴通讯股份有限公司 Loading method of software version and base station controller
US9973545B2 (en) * 2014-08-20 2018-05-15 At&T Intellectual Property I, L.P. Method and device for managing circuit switched data calls
US11582202B2 (en) 2015-02-16 2023-02-14 Arebus, LLC System, method and application for transcoding data into media files
US9964637B1 (en) 2015-04-17 2018-05-08 Lockheed Martin Corporation System and method for operating passive radar

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3700820A (en) * 1966-04-15 1972-10-24 Ibm Adaptive digital communication system
US4069392A (en) * 1976-11-01 1978-01-17 Incorporated Bell Telephone Laboratories Dual speed full duplex data transmission
US4384307A (en) * 1979-08-28 1983-05-17 Inteq, Inc. Facsimile communications interface adapter
US5199061A (en) * 1989-09-06 1993-03-30 Electronics And Telecommunications Research Institute Communication method and equipment for freeze-frame video phone

Family Cites Families (56)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US577984A (en) * 1897-03-02 Frank horovitz
US4125744A (en) * 1948-12-24 1978-11-14 Bell Telephone Laboratories, Incorporated Communication system
BE758187A (en) * 1969-11-13 1971-04-29 Cit Alcatel SIGNAL TRANSMITTING DEVICE IN PARTICULAR FOR NUMBERING KEYPAD
US3761610A (en) * 1971-02-16 1973-09-25 Graphics Sciences Inc High speed fascimile systems
US4385206A (en) * 1980-12-16 1983-05-24 Stromberg-Carlson Corporation Programmable port sense and control signal preprocessor for a central office switching system
JPS6010876A (en) * 1983-06-30 1985-01-21 Ricoh Co Ltd Facsimile communication control system
JPH0722324B2 (en) * 1983-08-30 1995-03-08 富士通株式会社 Data transmission method
US5351134A (en) * 1988-04-07 1994-09-27 Canon Kabushiki Kaisha Image communication system, and image communication apparatus and modem used in the system
US5105423A (en) * 1988-05-17 1992-04-14 Ricoh Company, Ltd. Digital transmission device having an error correction mode and method for shifting down a data transmission rate
US20010050943A1 (en) * 1989-08-03 2001-12-13 Mahany Ronald L. Radio frequency communication network having adaptive communication parameters
US7606575B2 (en) * 1988-08-04 2009-10-20 Broadcom Corporation Remote radio data communication system with data rate switching
US4959833A (en) * 1989-03-08 1990-09-25 Ics Electronics Corporation Data transmission method and bus extender
US5339174A (en) * 1989-05-02 1994-08-16 Harris Scott C Facsimile machine time shifting and converting apparatus
SE8903455D0 (en) * 1989-10-19 1989-10-19 Joakim Nelson DYNAMIC DIGITAL CONNECTION UNIT (DFN)
US5257283A (en) * 1989-11-07 1993-10-26 Qualcomm Incorporated Spread spectrum transmitter power control method and system
US5265119A (en) * 1989-11-07 1993-11-23 Qualcomm Incorporated Method and apparatus for controlling transmission power in a CDMA cellular mobile telephone system
US5056109A (en) * 1989-11-07 1991-10-08 Qualcomm, Inc. Method and apparatus for controlling transmission power in a cdma cellular mobile telephone system
US5267262A (en) * 1989-11-07 1993-11-30 Qualcomm Incorporated Transmitter power control system
AU627953B2 (en) * 1989-11-15 1992-09-03 Digital Equipment Corporation Integrated communications link having dynamically allocatable bandwidth and a protocol for transmission or allocation information over the link
US5050004A (en) * 1989-12-26 1991-09-17 At&T Bell Laboratories Facsimile machine transmission rate fall-back arrangement
US5115429A (en) * 1990-08-02 1992-05-19 Codex Corporation Dynamic encoding rate control minimizes traffic congestion in a packet network
US5230082A (en) * 1990-08-16 1993-07-20 Telefonaktiebolaget L M Ericsson Method and apparatus for enhancing signalling reliability in a cellular mobile radio telephone system
US5274474A (en) * 1991-01-23 1993-12-28 Randolph-Rand Corporation Integrated telefacsimile and character communication system with standard and high speed modes
US5315636A (en) * 1991-06-28 1994-05-24 Network Access Corporation Personal telecommunications system
ATE146637T1 (en) * 1991-11-08 1997-01-15 Calling Communications Corp BEAM COMPENSATION METHOD FOR SATELLITE COMMUNICATION SYSTEM
US5613228A (en) * 1992-07-06 1997-03-18 Micron Technology, Inc. Gain adjustment method in two-way communication systems
US5418624A (en) * 1992-09-02 1995-05-23 Ricoh Co., Ltd. Negotiation method and apparatus enabling a facsimile machine to use async data communication protocols
US5353332A (en) * 1992-09-16 1994-10-04 Ericsson Ge Mobile Communications Inc. Method and apparatus for communication control in a radiotelephone system
US5587715A (en) * 1993-03-19 1996-12-24 Gps Mobile, Inc. Method and apparatus for tracking a moving object
JP2503888B2 (en) * 1993-06-30 1996-06-05 日本電気株式会社 Data transmission method in mobile radio communication
US5771453A (en) * 1993-11-04 1998-06-23 Ericsson Inc. Multiple user base stations and methods for radio personal communications systems
US5491565A (en) * 1993-12-03 1996-02-13 Telefonaktiebolaget Lm Ericsson System and method for varying the transmission rate of facsimile data in a telecommunication system
US6018528A (en) * 1994-04-28 2000-01-25 At&T Corp System and method for optimizing spectral efficiency using time-frequency-code slicing
US5822318A (en) * 1994-07-29 1998-10-13 Qualcomm Incorporated Method and apparatus for controlling power in a variable rate communication system
EP0702474A1 (en) * 1994-09-19 1996-03-20 International Business Machines Corporation Dynamically structured data transfer mechanism in an ATM netowrk
FI96558C (en) * 1994-09-27 1996-07-10 Nokia Telecommunications Oy Method for data transmission in a TDMA mobile radio system and a mobile radio system for carrying out the method
US5604806A (en) * 1995-01-20 1997-02-18 Ericsson Inc. Apparatus and method for secure radio communication
US5533021A (en) * 1995-02-03 1996-07-02 International Business Machines Corporation Apparatus and method for segmentation and time synchronization of the transmission of multimedia data
US5563912A (en) * 1995-02-27 1996-10-08 Nec Corporation High efficiency speech coding apparatus and transit switching system employing the same
US5864587A (en) * 1995-06-06 1999-01-26 Lsi Logic Corporation Differential signal receiver
ZA965340B (en) * 1995-06-30 1997-01-27 Interdigital Tech Corp Code division multiple access (cdma) communication system
US7929498B2 (en) * 1995-06-30 2011-04-19 Interdigital Technology Corporation Adaptive forward power control and adaptive reverse power control for spread-spectrum communications
US5953346A (en) * 1996-06-27 1999-09-14 Interdigital Technology Corporation CDMA communication system which selectively suppresses data transmissions during establishment of a communication channel
US5805574A (en) * 1995-07-28 1998-09-08 Motorola, Inc. Adaptive switch resource allocation in a satellite communication system
US5744781A (en) * 1995-08-07 1998-04-28 General Electric Company Method and apparatus for laser shock peening
US5734646A (en) * 1995-10-05 1998-03-31 Lucent Technologies Inc. Code division multiple access system providing load and interference based demand assignment service to users
US5910949A (en) * 1995-10-18 1999-06-08 Telefonaktiebolaget Lm Ericsson Packet channel feedback
US5721725A (en) * 1995-10-30 1998-02-24 Xerox Corporation Protocol for channel access in wireless or network data communication
US5777984A (en) * 1996-04-01 1998-07-07 Motorola Inc. Method and apparatus for controlling cell transmission rate in a cell based network in the presence of congestion
US6324207B1 (en) * 1996-04-29 2001-11-27 Golden Bridge Technology, Inc. Handoff with closed-loop power control
US5864578A (en) * 1996-04-29 1999-01-26 Golden Bridge Technology, Inc. Matched filter-based handoff method and apparatus
US5872773A (en) * 1996-05-17 1999-02-16 Lucent Technologies Inc. Virtual trees routing protocol for an ATM-based mobile network
JP3294525B2 (en) * 1997-03-11 2002-06-24 株式会社日立テレコムテクノロジー Dynamic bandwidth allocation method
US6339626B1 (en) * 1998-03-16 2002-01-15 Ge Medical Systems Global Technology Company, Llc MRI system with fractional decimation of acquired data
JP2955561B1 (en) * 1998-05-29 1999-10-04 株式会社ディジタル・ビジョン・ラボラトリーズ Stream communication system and stream transfer control method
GB9821089D0 (en) * 1998-09-30 1998-11-18 Koninkl Philips Electronics Nv Method for the communication of information and apparatus employing the method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3700820A (en) * 1966-04-15 1972-10-24 Ibm Adaptive digital communication system
US4069392A (en) * 1976-11-01 1978-01-17 Incorporated Bell Telephone Laboratories Dual speed full duplex data transmission
US4384307A (en) * 1979-08-28 1983-05-17 Inteq, Inc. Facsimile communications interface adapter
US5199061A (en) * 1989-09-06 1993-03-30 Electronics And Telecommunications Research Institute Communication method and equipment for freeze-frame video phone

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SG108240A1 (en) * 2000-02-23 2005-01-28 Ntt Docomo Inc Multi-carrier cdma radio transmitting method and apparatus, and channel estimation method and apparatus for multi-carrier cdma radio transmitting system
US7457324B2 (en) 2000-02-23 2008-11-25 Ntt Docomo, Inc. Multi-carrier CDMA radio transmitting method and apparatus, and channel estimation method and apparatus for multi-carrier CDMA radio transmitting system
US7492794B2 (en) 2000-02-23 2009-02-17 Ntt Docomo, Inc. Channel estimation method and apparatus for multi-carrier radio transmitting system
US9525455B2 (en) 2002-04-29 2016-12-20 Interdigital Technology Corporation Simple and robust digital code tracking loop for wireless communication systems

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CA2259355A1 (en) 1997-12-31
US6744781B2 (en) 2004-06-01
US6965611B2 (en) 2005-11-15
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US20110058534A1 (en) 2011-03-10
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US20130308609A1 (en) 2013-11-21
JP2000514258A (en) 2000-10-24
US8699469B2 (en) 2014-04-15
US20020085544A1 (en) 2002-07-04
DE69710892D1 (en) 2002-04-11
US6741609B2 (en) 2004-05-25
US5953346A (en) 1999-09-14
DK0908036T3 (en) 2002-07-01
ES2137907T3 (en) 2002-11-01
ATE488066T1 (en) 2010-11-15
KR20040039385A (en) 2004-05-10
EP1152564A3 (en) 2004-08-04
PT908036E (en) 2002-08-30
EP1152564B1 (en) 2010-11-10
US7835308B2 (en) 2010-11-16
CN1223765A (en) 1999-07-21
US6608825B1 (en) 2003-08-19
US6741564B2 (en) 2004-05-25
US20040264401A1 (en) 2004-12-30
CN1118981C (en) 2003-08-20
ES2137907T1 (en) 2000-01-01
US20020089932A1 (en) 2002-07-11
US9247533B2 (en) 2016-01-26
EP1931078A2 (en) 2008-06-11
AU3496897A (en) 1998-01-14

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