A packet-based, hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. The network accommodates real time voice transmission both through dedicated, scheduled bandwidth and through a packet-based routing within the confines and constraints of a data network. Conversion and call processing circuitry is also disclosed which enables access devices and personal computers to adapt voice information between analog voice stream and digital voice packet formats as proves necessary. Routing pathways include wireless spanning tree networks, wide area networks, telephone switching networks, internet, etc., in a manner virtually transparent to the user. A voice session and associate call setup simulates that of conventional telephone switching network, providing well-understood functionality common to any mobile, remote or stationary terminal, phone, computer, etc.

Hierarchical Data Collection Network Supporting Packetized Voice Communications Among Wireless Terminals and Telephones

A financial information and transaction system utilizes wireless communication in connection with portable terminals. In this system, a terminal is connected to the financial institution via a wireless or cellular telephone hook-up. Smart cards are utilized to verify authorization for transactions, thereby minimizing potential security problems which could otherwise result from use of a mobile terminal. Alternately, a smart card is advantageously utilized not only for authorization, but also to maintain a secure record of available funds. The system not only provides the functionality of an ATM network, but also provides non-financial services, thereby forming an integrated system.

Wireless transaction and information system

An unlicensed wireless service (126) is adapted to generate the interface protocols of a licensed wireless service (106) to provide transparent transition of communication sessions between a licensed wireless service and an unlicensed wireless service. In one embodiment, a mobile station (102) includes level 1, level 2, and level 3 protocols for licensed wireless service and an unlicensed wireless service. An indoor base station (128) and indoor network controller provide protocol conversion for the unlicensed wireless service into a standard base station (108) controller interface of the licensed wireless service.

Apparatus and method for extending the coverage area of a licensed wireless communication system using an unlicensed wireless communication system

A communication network having at least one access point supports wireless communication among a plurality of wireless roaming devices via a first and a second wireless channel. The access point comprises a first and a second transceiver. The first and second transceivers operate on the first and second wireless channels, respectively. Each of the plurality of wireless roaming devices are capable of communicating on the first and second wireless channel. In one embodiment, the first wireless channel is used to exchange data, while the second channel is used to manage such exchanges as well as access to the first channel. In an alternate embodiment, both channels are used to support communication flow, however the first channel supports a protocol that is more deterministic than that of the second channel. Allocation of ones of the plurality of wireless roaming devices from one channel to the next may occur per direction from the access point. It may also result from decisions made by each of the wireless roaming devices made independent of the access point. For example, a decision may be made based on the data type being transferred or based on the current channel load. Such factors may also be used by the access point for allocation determinations. In addition, allocation may be based on the type of roaming device involved, such as allocating peripherals to a slower channel.

Local area network having multiple channel wireless access

A data transceiver module for digital data communications in a portable hand-held data terminal has multiple data spread spectrum modes which include direct sequence and frequency function modulation algorithms. The transceiver module has multiple user or program configurable data rates, modulation, channelization and process gain in order to maximize the performance of radio data transmissions and to maximize interference immunity. Various module housings, which may be PCMCIA type, are able to be mated with a suitably designed data terminal. Media access control protocols and interfaces of multiple nominal operational frequencies are utilized. Wireless access devices in a cell based network each consider a variety of factors when choosing one of a plurality of modes of wireless operation and associated operating parameters. Such selection defines a communication channel to support wireless data, message and communication exchanges. In further embodiments, the wireless access devices also support a second channel, a busy/control channel, for managing communication on the main communication channel and to overcome roaming and hidden terminal problems. Roaming terminal devices are also configured to support the dual channel design. Such configuration in both circumstances may involve the use of a multimode radio that is timeshared between the two channels or two radios, one dedicated to each channel.

Spread spectrum transceiver module utilizing multiple mode transmission

A technique for spread-spectrum communication which uses more than one mode and more than one frequency band. Selectable modes include narrowband mode and spread-spectrum mode, or cellular mode and microcellular mode. Selectable frequency bands include both licensed and unlicensed frequency bands, particularly frequency bands including the 902-928 MHz, 1850-1990 MHz, and 2.4-2.4835 GHz frequency bands. Spread-spectrum communication channels are 10 MHz or less in width. The frequency band onto which spread-spectrum signals are encoded may be changed upon a change in environment or other control trigger, such as establishment or de-establishment of communication with a private access network. A multi-band transmitter comprises a single frequency synthesizer and a frequency source (e.g., a local oscillator), coupled to a selectable band pass filter. A multi-band receiver capable of monitoring one or more frequency bands comprises bank of bandpass filters and a demodulator comprising a single frequency synthesizer and a frequency source.

Multi-band, multi-mode spread-spectrum communication system

A simple and flexible over-air protocol for use with a mobile telephone system, having hand-held telephones in a microcell or other type of cellular communication system. A method in which user stations communicate with one or more base stations to place and receive telephone calls, in which the user stations are provided a secure voice or data link and have the ability to handoff calls between base stations while such calls are in progress. Each base station has a set of “air channels” to which it transmits in sequence. The air channels supported by each base station are called that base station's “polling loop”. A user station receives general polling information on an unoccupied air channel, transmits responsive information to the base station, and awaits acknowledgment from the base station. Each base station may therefore simultaneously maintain communication with as many user stations as there are air channels in its polling loop. The ability of a user station to communicate on any unoccupied air channel makes the protocol air-channel agile, while the stability of user station and base station clocks may define air channels, gaps, and minor frames.

Spread spectrum communication system

A time division multiplexed wireless communication system using the DECT protocol with spread-spectrum modulation. The wireless communication system includes a spread-spectrum transmitter and receiver. The spread spectrum transmitter transmits using an M-ary spread spectrum transmission technique, sending a predefined chip code (symbol code) for each data symbol. The predefined chip codes used are relatively short, so that spread spectrum synchronization is accomplished within about a single data symbol transmission time, well within the constraints of the DECT timing structure. The spread spectrum signal may be transmitted over a bandwidth of under 20 MHz (e.g., about 5 MHz) covering a plurality of DECT frequency channels, so as to be confined within, or overlapping with, the bandwidth of a DECT system, and so as to minimize interference with other users, if any, of the same frequency spectrum. A spread spectrum transmission in a DECT time slot may overlay one or more narrowband transmissions, or may overlay other spread spectrum transmissions. Code division multiplexing may also be used to allow multiple spread spectrum transmissions to be sent during a single DECT time slot.

Spread spectrum communication system using DECT protocol

A system for publishing data (409) on shared broadcast channels using spread-spectrum techniques, which may comprise a spread-spectrum encoder (405) capable of receiving data and placing it in a spread-spectrum signal format (407) and a transmitter (406) operating on a shared communication channel or frequency band, such as might be allocated to terrestrial point-to-point or broadcast communications. The shared communication channel may comprise a cellular system, in which data (409) may be transmitted (406) using spread-spectrum techniques using the transmitters (406) and repeaters of the cellular system simultaneously with voice and other transmissions associated with the cellular system. A subscriber station may be capable of receiving using a plurality of different communication channels or frequency bands, such as a first receiver capable of cellular reception and a second receiver capable of satellite reception, at least one of which uses spread-spectrum techniques. The subscriber station may also comprise a transmitter using at least one communication channel or frequency band, so that the subscriber station may receive data or other transmissions using one channel and may request further data or other transmissions using a second channel.

Spread-spectrum data publishing system

A communication system (101) having a wireless trunk for connecting multiple phone stations (102) over wireless communication links to a cellular network. The communication system (101) comprises a central telephone switch (105) such as a private branch exchange or key system, connected through one or more trunk lines to a wireless access communication unit (106), and connected through a landline to a public switched telephone network (125). The wireless access communication unit (106) preferably comprises a separate subscriber interface (104) for each trunk line from the central telephone switch (105). The wireless access communication unit (106) collects data from each of the subscriber interfaces, formats the data into a format compatible with an over-the-air protocol, and transmits the information over one or more wireless channels (108) to a cellular base station (109). The wireless access communication unit (106) thereby provides the central telephone switch (105) with one or more channels to and from the cellular network.

Douglas G. Smith

Papers

Multi-band, multi-mode spread-spectrum communication system

Spread spectrum communication system

Spread spectrum communication system using DECT protocol

Spread-spectrum data publishing system

Communication system and method for addressing multiple capacity wireless trunk