Modular, portable data processing terminal for use in a radio frequency communication network

• US 7,537,167 B1
• Filed: 06/19/2000
• Issued: 05/26/2009
• Est. Priority Date: 08/31/1993
• Status: Expired due to Fees

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Miller, Phillip
• Primary Examiner(s): FRANKLIN, JAMARA ALZAIDA
• Application Number:
  US09/597,917
• Time in Patent Office: 3,263 Days
• Field of Search: 23547201-47203, 455 73- 88, 455550-575, 340/5.91, 340/7.42
• US Class Current: 235/472.01
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/163 Wearable computers, e.g. on a belt
• CPC Class Codes: G06F 1/1632 External expansion units, e.g. docking stations
• CPC Class Codes: G06F 1/1656 Details related to functional adaptations of the enclosure, e.g. to provide protection against EMI, shock, water, or to host detachable peripherals like a mouse or removable expansions units like PCMCIA cards, or to provide access to internal components for maintenance or to removable storage supports like CDs or DVDs, or to mechanically mount accessories mounting of accessories to a computer display G06F1/1607; display hoods G06F1/1603; cooling arrangements for portable computers G06F1/203
• CPC Class Codes: G06F 1/1698 the I/O peripheral being a sending/receiving arrangement to establish a cordless communication link, e.g. radio or infrared link, integrated cellular phone details of antennas disposed inside a computer H01Q1/2266
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/32 Means for saving power
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3228 Monitoring task completion, e.g. by use of idle timers, stop commands or wait commands
• CPC Class Codes: G06F 1/325 Power saving in peripheral device
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 15/0225 User interface arrangements, e.g. keyboard, display; Interfaces to other computer systems
• CPC Class Codes: G06F 2200/1632 Pen holder integrated in the computer
• CPC Class Codes: G06F 2200/1633 Protecting arrangement for the entire housing of the computer
• CPC Class Codes: G06F 3/0231 Cordless keyboards
• CPC Class Codes: G06F 3/04886 by partitioning the display area of the touch-screen or the surface of the digitising tablet into independently controllable areas, e.g. virtual keyboards or menus
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/006 the housing being a portable casing
• CPC Class Codes: G06K 7/10009 sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• CPC Class Codes: G06K 7/10386 : the interrogation device being of the portable or hand-handheld type, e.g. incorporated in ubiquitous hand-held devices such as PDA or mobile phone, or in the form of a portable dedicated RFID reader
• CPC Class Codes: G06K 7/10702 : Particularities of propagating elements, e.g. lenses, mirrors G06K7/10831 takes precedence
• CPC Class Codes: G06K 7/10722 : Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10841 : Particularities of the light-sensitive elements semiconductor devices H01L
• CPC Class Codes: G06K 7/10851 : Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03
• CPC Class Codes: G06K 7/1093 : sensing, after transfer of the image of the data-field to an intermediate store, e.g. storage with cathode ray tube
• CPC Class Codes: G06K 7/1098 : the scanning arrangement having a modular construction
• CPC Class Codes: G06K 7/12 : using a selected wavelength, e.g. to sense red marks and ignore blue marks
• CPC Class Codes: G06Q 10/08 : Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: G06Q 20/343 : Cards including a counter
• CPC Class Codes: G07F 7/02 : by keys or other credit registering devices
• CPC Class Codes: G07G 1/0045 : with a code reader for reading of an identifying code of the article to be registered, e.g. barcode reader or radio-frequency identity [RFID] reader
• CPC Class Codes: H01Q 1/007 : specially adapted for indoor communication
• CPC Class Codes: H01Q 1/2275 : associated to expansion card or bus, e.g. in PCMCIA, PC cards, Wireless USB
• CPC Class Codes: H01Q 1/24 : with receiving set
• CPC Class Codes: H01Q 1/241 : used in mobile communications, e.g. GSM H01Q1/247, H01Q1/248 take precedence
• CPC Class Codes: H01Q 1/273 : Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 21/24 : Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/29 : Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H02J 9/005 : using a power saving mode for copiers G03G15/5004
• CPC Class Codes: H04B 1/1615 : Switching on; Switching off, e.g. remotely battery saving circuits associated with selective call operation H04W52/00; details of power consumption reduction in a PLL, H03L7/0802, H03L7/14, H03L2207/08, H03L2207/18; muting amplifiers by gain control see H03G3/34
• CPC Class Codes: H04B 1/38 : Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
• CPC Class Codes: H04B 1/3816 : Mechanical arrangements for accommodating identification devices, e.g. cards or chips; with connectors for programming identification devices
• CPC Class Codes: H04B 1/3833 : Hand-held transceivers
• CPC Class Codes: H04B 1/3877 : Arrangements for enabling portable transceivers to be used in a fixed position, e.g. cradles or boosters
• CPC Class Codes: H04B 1/3883 : Arrangements for mounting batteries or battery chargers
• CPC Class Codes: H04B 17/0085 : using test signal generators
• CPC Class Codes: H04B 17/318 : Received signal strength
• CPC Class Codes: H04B 2001/3894 : Waterproofing of transmission device
• CPC Class Codes: H04L 1/0003 : by switching between different modulation schemes
• CPC Class Codes: H04L 1/0025 : Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0032 : Without explicit signalling
• CPC Class Codes: H04L 1/0071 : Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/1671 : the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1685 : the supervisory signal being transmitted in response to a specific request, e.g. to a polling signal
• CPC Class Codes: H04L 12/12 : Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 27/12 : Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 27/14 : Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 27/156 : with demodulation using temporal properties of the received signal, e.g. detecting pulse width
• CPC Class Codes: H04L 45/00 : Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/04 : Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/44 : Distributed routing
• CPC Class Codes: H04L 45/48 : Routing tree calculation
• CPC Class Codes: H04L 49/90 : Buffering arrangements
• CPC Class Codes: H04L 49/9073 : Early interruption upon arrival of a fraction of a packet
• CPC Class Codes: H04L 69/14 : Multichannel or multilink protocols
• CPC Class Codes: H04L 69/18 : Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/32 : Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 69/323 : in the physical layer [OSI layer 1]
• CPC Class Codes: H04L 69/324 : in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04L 69/325 : in the network layer [OSI layer 3], e.g. X.25 H04L69/16 takes precedence
• CPC Class Codes: H04L 69/326 : in the transport layer [OSI layer 4] H04L69/16 takes precedence
• CPC Class Codes: H04L 69/327 : in the session layer [OSI layer 5]
• CPC Class Codes: H04L 9/40 : Network security protocols
• CPC Class Codes: H04M 1/0254 : comprising one or a plurality of mechanically detachable modules
• CPC Class Codes: H04M 7/006 : Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04W 52/0209 : in terminal devices terminal devices per se H04W88/02
• CPC Class Codes: H04W 52/0277 : according to available power supply, e.g. switching off when a low battery condition is detected
• CPC Class Codes: H04W 52/0293 : having a sub-controller with a low clock frequency switching on and off a main controller with a high clock frequency
• CPC Class Codes: H04W 88/02 : Terminal devices
• CPC Class Codes: H04W 88/06 : adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02B 70/30 : Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02D 10/00 : Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/70 : in wireless communication networks
• CPC Class Codes: Y04S 20/20 : End-user application control systems

Abstract

Modular, portable data collection terminals are disclosed for use in mixed wireless and hard-wired RF communication networks, wherein various radio transmitter modules and associated antennas may be selectively added to a base terminal unit to solve networking problems associated with specific types of business environments. Modularity exists in both the hardware (splitting data collection and processing control circuitry from radio transceiver control circuitry) and software (splitting transceiver-specific, lower level communication protocol from generic, higher level communication protocol). The control circuitry, including associated microprocessors devices, interact to selectively activate communication circuits to perform necessary communication or data processing functions and enter and remain in a power-saving dormant state during other times. To support such dormant or “sleeping” states, a series of communication protocols provide for channel access to the communication network. The disclosed modular design also provides for automatic selection from a variety of available built-in and externally mounted antennas based on the particular type of radio transceiver(s) selected.

Claims

1. In a local area communications network having a communication channel, a host computer, an access point, and a portable terminal, wherein the portable terminal has the capability to enter a sleep mode when not transmitting or receiving, and the access point periodically transmits synchronization messages, a method used by the portable terminal for gaining access to the communication network, comprising:

(a) waking up when data is available for transmission to the host computer;

(b) waiting for a first predetermined time in order to receive a synchronization message from the access point;

(c) sensing the communications channel for a second predetermined time to determine if the channel is busy;

(d) transmitting a request for poll to the access point if the channel is clear for the second predetermined time; and

(e) if the channel is busy during the second predetermined time, repeating operation (b).

2. The method of claim 1, wherein said first predetermined time is greater than or equal to the time between synchronization messages minus the maximum interpoll gap time.

3. The method of claim 1, wherein said second predetermined fixed time is greater than or equal to the maximum interpoll gap time.

4. A method used by a sending device for beginning a data exchange over an RF communication link with a polling device, wherein the polling device has an interpoll gap time, comprising:

(a) generating a pseudo-random number corresponding to a first pseudo-random time which is at least as long as the interpoll gap time;

(b) sensing a channel for a time substantially shorter than the first pseudo-random time;

(c) repeating operation (b) until the channel is detected as being busy, or the channel is detected as being clear at every sense until the first pseudo-random time is reached;

(d) if the channel is detected as being busy, executing a second pseudo-random time delay back-off and returning to operation (a); and

(e) if the channel has been detected as being clear for the entire first pseudo-random time period, transmitting a request for poll frame.

5. The method of claim 4 wherein operation (d) further comprises incrementing a retry counter and testing said retry counter such that a second pseudo-random back-off and retry will not be performed if said retry counter is above a predetermined threshold value.