Diversity transmission strategy in mobile/indoor cellula radio communications

• US 5,507,035 A
• Filed: 04/30/1993
• Issued: 04/09/1996
• Est. Priority Date: 04/30/1993
• Status: Expired due to Term

• Current Assignee: NETGEAR, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Moulton, Nicholas J. A., Huang, Chia-Chi, Bauchot, Frederic J., Bantz, David F.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): TO, DORIS HA
• Application Number:
  US08/056,163
• Time in Patent Office: 1,075 Days
• Field of Search: 455/52.3, 455/52.1, 455/65, 455/101, 455/133, 455/134, 455/136, 455/140, 455/275, 455/277.1, 455/277.2, 455/33.1, 455/33.3, 375/40, 375/100, 375/347, 375/299
• US Class Current: 455/133
• CPC Class Codes: H04B 7/0814 based on current reception conditions, e.g. switching to different antenna when signal level is below threshold
• CPC Class Codes: H04B 7/0817 with multiple receivers and antenna path selection

Abstract

In a mobile cellular communication system, a base station is wired to a Local Area Network (LAN), and has wireless communication with a plurality of mobile stations. Multipath fading is substantially reduced in the system by utilizing antenna diversity techniques at the base station and each of the plurality of mobile stations. The combination of the independent operation of antenna selection diversity at both a base station and a mobile station results in the selection of the best propagation path between the two stations.

Claims

1. In a diversity transmission system for wireless radio communications between a base station and at least one mobile station, the combination:

multiple antennas at said base station and said at least one mobile station for transmission of data between the respective stations;

means in the base station for determining which one of said multiple antennas received data most successfully, during a last reception by said base station with this antenna being referred to as a preferred antenna of said base station;

means in said at least one mobile station for selecting one of said multiple antennas in such mobile station as a preferred antenna for said mobile station based on its use to successfully receive data during the last reception by that mobile station;

a preferred antenna storage means in the base station and in at least one mobile station in which is stored indicia indicative of which antenna at such station is determined to be the preferred antenna;

a controller at said base station and said at least one mobile station which is responsive to said indicia stored in the preferred antenna storage means for controlling the transmission of data between the respective stations by selecting the preferred antenna at the respective stations;

means in the base station and at least one mobile station to select one of the multiple antennas of that station as the preferred antenna in absence of said stored indicia;

means in said base station for repeating a transmission until an acknowledgement of such transmission from said at least one mobile station is received or until a predetermined number of such repeated transmissions are performed; and

means for changing the preferred base station antenna for each such repeated transmission.

2. The combination claimed in claim 1 including:

means in said mobile station for signalling a failure to said at least one mobile station when said acknowledgment of reception of the data is not received after said predetermined number of transmissions of the data.

3. The diversity transmission system of claim 1 including:

means for storing data received during said last reception from each of the multiple antennas at said base station; and

means for selecting the data from the said one of said multiple antennas that received data most successfully at said base station for use after said last reception is complete.

4. The diversity transmission system of claim 1 wherein said means for determining which of said multiple antennas in said base station and said at least one mobile station received signals most successfully is a means for measuring received signal strength to make the determination.

5. The diversity transmission system of claim 1 wherein said means for determining which of said multiple antennas in said base station received signals most successfully includes error correction means to make the determination.

6. A diversity transmission system for determining the best wireless communication path between a base station and a mobile station, comprising:

at least two base station antennas for transmission of data between said base station and said mobile station;

means for determining which of said at least two base station antennas receives transmitted data most successfully from said mobile station, with this antenna being referred to as a preferred base station antenna;

a base station storage means for storing indicia indicative of which base station antenna is determined to be the preferred base station antenna;

means responsive to stored indicia in said base station storage means for selecting the preferred base station antenna for a next transmission of data from said base station to said mobile station;

means in said base station to randomly select one of the at least two antennas at the base station as the preferred antenna for said next transmission in the absence of said stored indicia;

means for repeating transmissions of data of said next transmission until an acknowledgement of data reception is received from said mobile system or until a predetermined number of such repeated transmissions are performed;

means for changing which of said at least two base station antennas is the preferred base station antenna for each such repeated transmission;

means signaling failure to said base station when an acknowledgement of reception is not received after the predetermined number of repeated transmissions are performed without success;

means for changing the preferred base station antenna for the transmission of the data if a later reception at the base station is more successfully received on other than on a then preferred base station antenna;

means for updating the indicia stored in said base station storage means to reflect the change in said preferred base station antenna

at least two mobile station antennas for transmission of data between said mobile station and said base station;

means for determining if one of said at least two mobile station antennas receives transmitted data successfully from said base station, with this antenna being referred to as a preferred mobile station antenna;

a mobile station storage means in which is stored indicia indicative of which mobile station antenna is determined to be the preferred mobile station antenna;

means responsive to stored indicia in said mobile station storage means for selecting the preferred mobile station antenna for transmission of data from said mobile station to said base station;

means in said mobile station to randomly select one the at least two antennas at the mobile station as preferred the preferred mobile station or antenna for transmission in absence of said stored indicia;

means for changing the preferred mobile station antenna if an acknowledgement of reception of data isn'"'"'t received from the base station;

means for updating the indicia stored in said mobile station storage means to reflect the change in said preferred mobile station antenna; and

means in said mobile station for signalling a failure to said mobile station when said acknowledgement of reception of data is not received from said base station following a predetermined number of transmissions of data from said mobile station to said base station.

7. In a diversity transmission system for wireless radio communications between a base station and a plurality of mobile stations, the combination of:

at least two base station antennas at said base station for transmission of data between said base station and said plurality of mobile stations;

at least two base station radio transceivers located at said base station with each such transceiver being connected to a different one of said at least two base station antennas;

means of determining which one of said at least two base station transceivers received data most successfully during a last reception by said base station from each of said plurality mobile stations, with this transceiver being referred to as a preferred base station transceiver with respect to a mobile station it is receiving data from;

a preferred base station transceiver storage means in said base station controller, in which is stored indicia indicative of which base station transceiver is determined to be the preferred base station transceiver with respect to each of said plurality of mobile stations;

means responsive to stored indicia in said preferred base station transceiver storage means for selecting the preferred base station transceiver for transmission of data from said base station to a given mobile station of said plurality of mobile stations;

means for changing the preferred base station transceiver for said given mobile station if an acknowledgement of reception of data from said given mobile station isn'"'"'t received, or if the acknowledgement is received more successfully on a base station transceiver other than said preferred transceiver;

means in said base station for signalling a failure at said base station when said acknowledgement of reception of data is not received from a given mobile station following a predetermined number of transmissions of the data from said base station to said given mobile station using different ones of said at least two base station transceivers;

means for updating the indicia stored in said preferred base station to reflect the change in preferred antenna for said given mobile station;

at least two mobile station antennas at each of said plurality of mobile stations for transmission of data between said plurality of mobile stations and said base station;

a mobile station radio transceiver located at each of said plurality of mobile stations, which is selectively connected to said at least two mobile station antennas;

means for determining which one of said at least two mobile station antennas at each of said plurality of mobile stations, received data most successfully during a last transmission from said base station, with this mobile station antenna being referred to as a preferred mobile station antenna;

a preferred mobile station antenna storage means at each of the plurality of mobile stations in which is stored indicia indicative of which mobile station antenna at that station is determined to be the preferred mobile station antenna;

means, at each of said plurality of mobile stations which is responsive to the stored indicia in said preferred mobile station antenna storage means for selectively connecting said mobile station radio transceiver to the preferred mobile station antenna for controlling the transmission of data between a mobile station and said base station; and

means in the base station and at each of the plurality of mobile stations to select one of the transceivers at that station to act as the preferred transceiver in absence of stored indicia as to the transceiver that received data more successfully.

9. In a diversity transmission system for wireless radio communications between a base station and a plurality of mobile stations, the combination of:

at least two base station antennas at said base station for transmission of data in data packets between said base station and said plurality of mobile stations;

a base station radio transceiver which is selectively connected to said at least two base station antennas;

means for determining which one of said at least two base station antennas received data most successfully during a last data packet transmission from each of said plurality of mobile stations, with this antenna being referred to as a preferred base station antenna with respect to a mobile station it is receiving data from;

a preferred base station antenna storage means, in which is stored a plurality of indicia each one indicative of which base station antenna is determined to be the preferred base station antenna with respect to a different one of said plurality of mobile stations;

means responsive to stored indicia in said preferred base station antenna storage means for selectively connecting said base station radio transceiver to the preferred antenna for controlling the transmission and reception of data between said base station and each of said plurality of mobile stations;

means for changing the preferred base station antenna for a given mobile station if an acknowledgement of reception of data from said given mobile station isn'"'"'t received within a predetermined time, or if the acknowledgement is received more successfully on a base station antenna other than said preferred antenna;

means for updating the indicia stored in said preferred base station antenna storage means to reflect the change in preferred antenna for said given mobile station;

at least two mobile station antennas at each one of said plurality of mobile stations for transmission of data in data packets between said plurality of mobile stations and said base station;

a mobile station radio transceiver located at each of said plurality of mobile stations, which is selectively connected to said at least two mobile station antennas;

means for determining which one of said at least two mobile station antennas at each of said plurality of mobile stations received data most successfully during a last data packet transmission from said base station, with this mobile station antenna being referred to as a preferred mobile station antenna;

a preferred mobile station antenna storage means in which is stored indicia indicative of which mobile station antenna is determined to be the preferred mobile station antenna;

means at each of said plurality of mobile stations, which is responsive to the stored indicia in said preferred mobile station antenna storage means for selectively connecting said mobile station radio transceiver to the preferred mobile station antenna for controlling the transmission and reception of data between a mobile station and said base station; and

means at the stations to select at random one of the antennas at the stations to act as the preferred antenna for any station where there is an absence of stored indicia as to an antenna that received data more successfully.

8. The combination claimed in claim 11 including:

means in said mobile station for signalling a failure at said given mobile station when an acknowledgement of reception of data is not received from said base station following a predetermined number of transmissions of the data from said given mobile station to said base station.

10. The combination claimed in claim 9, including:

means in said base station for signalling a failure at said base station when said acknowledgement is not received from a given mobile station following a predetermined number of transmissions of the data from said base station to said given mobile station.

11. The combination claimed in claim 10, including:

means in said mobile station for signalling a failure at said given mobile station when an acknowledgement is not received from said base station following a predetermined number of transmissions of the data from said given mobile station to said base station.