Subscriber RF telephone system for providing multiple speech and/or data signals simultaneously over either a single or a plurality of RF channels

• US 6,014,374 A
• Filed: 09/09/1997
• Issued: 01/11/2000
• Est. Priority Date: 03/20/1985
• Status: Expired due to Fees

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Handzel, Mark J., Paneth, Eric, Morley, Steven Allan, Avis, Graham M.
• Primary Examiner(s): TSE, YOUNG TOI
• Application Number:
  US08/926,405
• Time in Patent Office: 854 Days
• Field of Search: 375/219, 375/222, 375/240, 375/259, 375/377, 370/330, 370/336, 370/337, 370/345, 370/347, 370/436, 370/442, 370/465, 370/468, 370/478, 370/498, 370/537, 370/540, 370/522, 455/403, 455/418, 455/419, 455/422, 455/450, 455/452, 455/507, 455/509, 455/511, 455/514, 455/517, 455/550, 455/561
• US Class Current: 370/345
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0865 Independent weighting, i.e. weights based on own antenna reception parameters
• CPC Class Codes: H04J 3/0647 Synchronisation among TDM nodes
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0084 Formats for payload data
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1642 Formats specially adapted for sequence numbers
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/143 for modulated signals H04L5/1469 takes precedence
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 28/14 : using intermediate storage
• CPC Class Codes: H04W 28/24 : Negotiating SLA [Service Level Agreement]; Negotiating QoS [Quality of Service]
• CPC Class Codes: H04W 28/26 : Resource reservation
• CPC Class Codes: H04W 36/12 : Reselecting a serving backbone network switching or routing node
• CPC Class Codes: H04W 4/18 : Information format or content conversion, e.g. adaptation by the network of the transmitted or received information for the purpose of wireless delivery to users or terminals
• CPC Class Codes: H04W 40/02 : Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 52/0216 : using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/20 : using error rate
• CPC Class Codes: H04W 56/00 : Synchronisation arrangements
• CPC Class Codes: H04W 72/02 : Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/04 : Wireless resource allocation
• CPC Class Codes: H04W 72/044 : based on the type of the allocated resource
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/12 : Wireless traffic scheduling
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/04 : Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 76/10 : Connection setup
• CPC Class Codes: H04W 84/00 : Network topologies
• CPC Class Codes: H04W 84/14 : WLL [Wireless Local Loop]; RLL [Radio Local Loop]
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A telecommunication system for processing a plurality of simultaneous bidirectional communications includes a primary station and at least one secondary station using wireless transmissions over one of a plurality of available RF carrier frequencies. Each carrier frequency has an associated predetermined bandwidth which is designed to accommodate one analog voice signal therein and each carrier frequency contains a plurality of time slots. Each bidirectional communication includes transmit (TX) and receive (RX) information signals. The secondary stations include a baseband processor for PSK coding an input signal; a storage means coupled to said baseband processor for storing information; a control means coupled to the baseband processor and the storage means to permit access to the stored information; a filter for performing quadrature sampling of the PSK coded signal; a digital to analog converter for converting the sampled PSK coded signal into an analog signal; and a frequency translator for translating the frequency spectrum of the analog signal to a second frequency spectrum.

Claims

1. In a telecommunication system for processing a plurality of simultaneous bidirectional communications between a primary station and at least one secondary station using wireless transmissions over one of a plurality of available RF carrier frequencies, each carrier frequency having an associated predetermined bandwidth which is designed to accommodate one analog voice signal therein and each carrier frequency containing a plurality of time slots;

each bidirectional communication comprising transmit (TX) and receive (RX) information signals, said at least one secondary station comprising;

a baseband processor for controlling the functions of said secondary station, the processor having;

means for receiving an input signal constituting a digitized bit stream; and

means for PSK coding said input signal in accordance with a predetermined code;

storage means coupled to said baseband processor for storing information associated with the functions controlled by said baseband processor including said baseband processor PSK coding means;

control means coupled to said baseband processor and said storage means to permit access to said information stored in said storage means;

said control means being coupled to a programming means for programming said control means to perform various control functions;

a timing generator for outputting a timing signal;

filter means for performing time multiplexed quadrature sampling of the PSK coded signal;

a digital to analog converter for receiving said time multiplexed quadrature sampled PSK coded signal and converting it into an analog signal; and

frequency translator means for mixing of the analog signal with an IF signal and translating the entire frequency spectrum of the analog signal to a second frequency spectrum to provide an IF output signal.

2. The system of claim 1, wherein said baseband processor further includes means for performing echo cancellation.

3. The system of claim 1 further comprising a demodulator coupled to the control means for converting a received modulated IF signal to a digitized bit stream.

4. The system of claim 1 wherein said digitized bit stream appears in repetitive frames, and wherein at least a portion of a first half of each frame constitutes a receive mode and at least a portion of a corresponding second half of each frame constitutes a transmit mode, each of said portions comprising a slot, each of said slots containing a unique word for establishing timing for reception of the communications in the slot.

5. A telecommunication system for processing a plurality of simultaneous bidirectional communications between a primary station and at least one secondary station using wireless transmissions over one of a plurality of available RF carrier frequencies, each carrier frequency having an associated predetermined bandwidth which is designed to accommodate one analog voice signal therein and each carrier frequency containing a plurality of time slots;

each bidirectional communication comprising transmit (TX) and receive (RX) information signals, the primary station comprising;

a baseband processor comprising;

means for receiving an input signal constituting a digitized bit stream in which a given number of successive bits defines a symbol;

means for PSK coding said input signal in accordance with a predetermined code; and

means for controlling selected functions of said primary station;

a storage unit coupled to said baseband processor for storing information associated with the functions controlled by said baseband processor and for storing information associated with said means for PSK coding said input signal;

a controller coupled to said baseband processor in a manner permitting said controller to access said baseband processor and to obtain said information stored in said storage unit;

a programmer, coupled to said controller, which programs said controller to perform its functions;

a digital to analog converter for receiving the coded digitized bit stream from the baseband processor and for converting the coded digitized bit stream into an analog signal which is then provided at an IF frequency;

a frequency synthesizer having first and second outputs, wherein said first output is offset from said second output by a predetermined frequency;

said first output for combining with a signal at the IF frequency to provide a signal of a predetermined desired RF frequency; and

said second output for combining with a received signal to produce a signal having the same frequency as said IF signal; and

an amplifier for converting said RF signal to an amplified RF analog signal.

6. A system as in claim 5 wherein said predetermined frequency is 5 megahertz.

7. A subscriber system for a wireless digital telephone system for providing voice signals on one or more forward and reverse direction RF carrier frequencies in an RF telephone system, at least one of said forward and reverse direction RF carrier frequencies is assigned, each of said forward and reverse RF carrier frequencies containing a plurality of slots, each of said forward and reverse direction RF carrier frequencies having an associated predetermined bandwidth which is designed to accommodate one analog voice signal channel therein, said subscriber system having circuit paths for accommodating a forward direction digitized voice signal from a base station and reverse direction digitized voice signal from a subscriber, said circuit paths comprising:

a compressor/decompressor for respectively compressing a reverse direction voice signal to form a compressed reverse direction signal and decompressing a compressed forward direction signal to provide a forward direction voice signal;

a multiplexer/demultiplexer for respectively multiplexing the compressed reverse direction signal into sequential time slots in a reverse direction transmit channel bit stream and demultiplexing signals from sequential time slots in a forward direction transmit channel bit stream into the compressed forward direction signal;

a modulator/demodulator for respectively modulating the reverse direction transmit channel bit stream into a reverse direction IF frequency and demodulating a forward direction IF frequency into the forward direction transmit channel bit stream; and

a radio frequency unit having a pair of frequency outputs wherein a first output is offset from the second output by a predetermined frequency, the first output for combining with a received forward RF carrier frequency to provide the forward direction IF frequency and the second output for combining with the reverse direction IF frequency to provide a reverse direction RF carrier frequency, whereby the forward and reverse direction RF carrier frequencies are separated by said predetermined frequency.

8. A subscriber system as in claim 7 and further comprising means for extracting a signal received from a base station providing information relating to the assignment of at least one of the forward and reverse direction RF carrier frequencies and producing a reference signal to said radio frequency unit whereby said radio frequency unit determines the appropriate frequency levels for said first and second output.

9. A system as in claim 7 wherein the forward frequency is less than the reverse frequency by said predetermined frequency.