Wireless network for wideband indoor communications

• US 4,789,983 A
• Filed: 03/05/1987
• Issued: 12/06/1988
• Est. Priority Date: 03/05/1987
• Status: Expired due to Term

• Current Assignee: Avaya Technology Corporation Miami Lakes FLA US
• Original Assignee: American Telephone & Telegraph Company (AT&T, Inc.)
• Inventors: Winters, Jack H., Acampora, Anthony
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Marcelo, Melvin
• Application Number:
  US07/022,255
• Time in Patent Office: 642 Days
• Field of Search: 370/94, 370/95, 370/96, 370/109, 370/29, 370/13.1, 370/17, 370/97, 370/84, 379/58, 379/61, 379/63, 371/5
• US Class Current: 370/349
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04W 74/06 using polling

Abstract

The present invention relates to a wideband communication network using wireless radio transmissions either on a stand-alone basis or to supplement a hard-wired network. The exemplary network comprises (a) a plurality of transceivers associated with separate users of the network; (b) optionally at least one concentrator associated with certain separate subgroups of wireless and possibly hard-wired transceivers for providing duplex operation; and (c) a central node (i) capable of providing both duplex communications directly via a radio channel using radio links with certain subgroups of the transceivers and via a hard-wired connection with each optional concentrator, and (ii) for polling the needs of all transceivers and directing all packets of information from active transceivers through the central node and to the destined transceivers during each frame period. The network also preferably includes diversity and resource sharing techniques to provide added protection against channel impairments on an as-needed basis.

Claims

1. A wideband packet communication network comprising:

a plurality of transmitters (10-19), each transmitter being associated with a separate user or group of users of the network for transmitting packets of information between an active user or group of users and the network via either one of a hard-wired or wireless connection during a frame period; and

a central node (30) for communicating with each of the plurality of transmitters via the hard-wired or wireless connection, the central node comprising,

processor means (35) for (a) determining packet transmission requirements associated with each transmitter communicating with the central node via a wireless connection during a first subperiod of each frame period, (b) causing each wireless transmitter determined to have a packet transmission requirement, to transmit its packets of information during a separate second subperiod of time of each frame period, (c) detecting during the first and/or second subperiods of each frame period, transmission impairments associated with each wireless transmitter, and (d) causing packets of information transmitted from each transmitter determined to have a transmission impairment to be transmitted at a transmission rate sufficient to lessen the determined transmission impairment, and

means (32-34) for (a) receiving packets of information from the plurality of transmitters of the network, and (b) retransmitting the packets to receivers associated with the destined users of the packets of information via an appropriate hard-wired or wireless connection.

2. A wideband packet communication network according to claim 1 wherein the receiving and retransmitting means comprises:

a high-speed bus for propagating packets of information from the plurality of transmitters on a time division multiplexed basis; and

a plurality of network interface units (NIUs), each NIU being associated with a separate subgroup of one or more of the plurality of transmitters, and connected to the tramsitters of the separate subgroup via a wireless communication link or separate hard-wired connections for receiving the packets of information from the associated subgroup of transmitters and transmitting each packet over the high-speed bus during a free time slot period to the NIU associated with a user destined to receive the packet of information.

3. A wideband packet communication network according to claim 2 wherein the network further comprises:

at least one concentrator, each concentrator being disposed between a separate subgroup of the plurality of transmitters and a predetermined one of the plurality of NIUs, each concentrator comprising;

a plurality of user interface modules (UIM), each UIM providing duplex communications with a separate portion of the subgroup of transmitters associated with the concentrator, where at least one of the subgroup portions communicates with its UIM via a separate wireless link,

a trunk module for providing duplex communications between the UIMs of the concentrator and the predetermined associated one of the plurality of NIUs in the central node on a time division multiplexed basis, and

a bus for propagating packets of information between the plurality of UIMs of the concentrator and the trunk module on a time division multiplexed basis.

4. A wideband packet communication network according to claim 1, 2 or 3 wherein the processor means comprises:

means responsive to the beginning of a frame period for (a) sequentially sending first control signals (P_i) to each of the plurality of transmitters and sequentially receiving second control signals (R_i) from the transmitters indicative of whether or not a transmitter has a packet of information to be transmitted during the frame period, and (b) in response to each received second control signal indicating that a transmitter is active and has a packet of information to be sent, sequentially transmitting third control signals (TS_i) to the active transmitters for causing the packet of information to be sent by the transmitter for routing by the central node to a destined user of the packet of information.

5. A wideband packet communication network according to claim 4 wherein

the receiving and retransmitting means in the central node comprises means for detecting that a packet of information was received from a transmitter with a bit error rate that is less than a predetermined value, and for generating a separate transmission impairment control signal to the determining and causing means;

and

the determining and causing means is responsive to a transmission impairment control signal from the receiving and retransmitting means for transmitting a subsequent second control signal to the transmitter detected as having a transmission impairment for causing the transmitter to retransmit the packet of information at a slower data rate using a predetermined resource sharing technique.

6. A wideband packet communication network according to claim 5 wherein

the receiving and retransmitting means includes diversity antennas associated with wireless connections.

7. A wideband packet communication network according to claim 1,2 or 3 wherein

the receiving and retransmitting means includes diversity antennas associated with the wireless connections.

8. A method of transmitting information between a plurality of transmitters and a central node, including a processor means, via either one of a hard-wired or wireless connection during a frame period in a wideband packet communication network, each transmitter being associated with a separate user or group of users of the network, the method comprising the steps of:

(a) the processor means in the central node determining the packet transmission requirements of each transmitter communicating with the central node during a first subperiod of time of each frame period;

(b) causing a wireless transmitter determined in step (a) to have packet transmission requirements, to transmit its packets of information during a separate second subperiod of time of each frame period;

(c) the processor means detecting, during the first and/or second subperiods of time of each frame period, transmission impairments associated with each wireless transmitter; and

(d) the processor means causing packets of information transmitted from each transmitter determined to have a transmission impairment in step (c) to be transmitted at a transmission rate sufficient to lessen the determined transmission impairment.

9. A method according to claim 8 wherein the method comprises the further steps of:

in performing step (a) performing the substeps of

(a1) the processor means sequentially transmitting first control signals (P_i) to each of the plurality of transmitters, and

(a2) sequentially receiving second control signals (R_i) from the plurality of transmitters indicative of whether or not a transmitter has a packet of information to be transmitted during the frame period; and

in performing step (b), performing the step of

(b1) in response to each received second control signal in step (a2) indicating that a transmitter is active and has a packet of information to be sent, sequentially transmitting third control signals (TS_i) to the active transmitters for causing the packet of information to be sent by the transmitter for routing by the central node to a destined user of the packet of information.

10. A method according to claim 8 or 9 wherein in performing step (c) performing the substeps of:

(c1) detecting at the central node that a packet of information was received from a transmitter with a bit error rate that is less than a predetermined value;

(c2) transmitting a subsequent second control signal to the transmitter detected as having a transmission impairment in response to the detection of a bit error rate more than a predetermined value in step (c1); and

(c3) a transmitter having a transmission impairment being responsive to a subsequent second control signal transmitted in step (c2) for retransmitting the packet of information at a slower transmission rate using a predetermined resource sharing technique such that the packet of information is received at the central node with a bit error rate below the predetermined value.