Radio calling method and apparatus for removing near-far problem

Claim 2

A radio calling method for removing a near-far problem in a radio switching system which groups a plurality of cordless fixed parts distributed in various areas at least first and second groups and controls communication of the groups with a cordless portable part, which is comprised of the steps of: (a) when a cordless portable part disposed between a first group and a second group attempts an outgoing call, scanning a channel by the cordless fixed part belonging to each group for the purpose of finding the channel where the cordless portable part has attempted to transmit the outgoing call; (b) fixing the frequency of the cordless fixed parts at that channel and comparing a received field strength with a predetermined communication field strength; (c) when the received field strength is more than the communication field strength, storing the received field strength and determining whether or not link-request data has been received during a given period of time; (d) when the link-request data has been received during the given period of time, determining whether or not the received field strength is more than a predetermined near-far field strength and, when the received field strength is more than the near-far field strength, transmitting a link-grant to the cordless portable part which has attempted the outgoing call; and (e) when the received field strength is less than the near-far field strength, comparing a received cordless portable part ID with a cordless portable part ID of link-request data which has been previously received and stored in memory, and increasing count in a corresponding counter when the received cordless portable part ID is equal to the cordless portable part ID of the link-request data, and comparing the increased count in the counter with a predetermined count, and transmitting a link-grant to the cordless portable part which has attempted the outgoing call, when the increased count in the counter is more than the predetermined count.

Claim 3

The method as set forth in claim 1, said method further comprising the step of returning to step (a) when the link-request data has not been received during a given period of time.

Claim 4

A radio calling method for removing a near-far problem in a radio switching system which groups a plurality of cordless fixed parts distributed in various areas into at least first and second groups and controls communication of the groups with a cordless portable part, which is comprised of the steps of: (a) when a cordless portable part disposed between a first group and a second group attempts an outgoing call, scanning a channel by the cordless fixed part belonging to each group for the purpose of finding the channel where the cordless portable part has attempted to transmit the outgoing call; (b) fixing the frequency of the cordless fixed parts at that channel and comparing a received field strength with a predetermined communication field strength; (c) when the received field strength is more than the communication field strength, storing the received field strength and determining whether or not link-request data has been received during a given period of time; (d) when the link-request data has been received during the given period of time, determining whether or not the received field strength is more than predetermined a near-far field strength and, when the received field strength is more than the near-far field strength, transmitting a link-grant to the cordless portable part which has attempted the outgoing call; and (e) when the received field strength is less than the near-far field strength, comparing a received cordless portable part ID with a cordless portable part ID of link-request data which has been previously received and stored in a memory, and determining whether or not a time-out of a corresponding timer has occurred when the received cordless portable part ID is equal to the cordless portable part ID of the link-request data, and transmitting a link-grant to the cordless portable part which has attempted the outgoing call, when the time-out of the corresponding timer has occurred.

Claim 5

A radio calling method for removing a near-far problem in a radio switching system which groups a plurality of cordless fixed parts distributed in various areas into at least first and second groups and controls communication of the groups with a cordless portable part, which is comprised of the steps of: (a) when a cordless portable part disposed between a first group and a second group attempts an outgoing call, scanning a channel by the cordless fixed part belonging to each group for the purpose of finding the channel where the cordless portable part has attempted to transmit the outgoing call; (b) fixing the frequency of the cordless fixed parts at that channel and comparing a received field strength with a predetermined communication field strength; (c) when the received field strength is more than the communication field strength, storing the received field strength and determining whether or not link-request data has been received during a given period of time; (d) when the link-request data has been received during the given period of time, determining whether or not the received field strength is more than predetermined a near-far field strength and, when the received field strength is more than the near-far field strength, transmitting a link-grant to the cordless portable part which has attempted the outgoing call; and (e) when the received field strength is less than the near-far field strength, comparing a received cordless portable part ID with a cordless portable part ID of link-request data which has been previously received and stored in a memory, and determining whether or not a time-out of a corresponding timer has occurred when the received cordless portable part ID is equal to the cordless portable part ID of the link-request data, and transmitting a link-grant to the cordless portable part which has attempted the outgoing call, when the time-out of the corresponding timer has occurred.

Claim 6

A radio calling apparatus for removing near-far problem in a radio switching system grouping a plurality of cordless fixed parts distributed in various areas in to at least first and second groups and controls communication of the groups with a cordless portable part, said apparatus comprising: a scanner for scanning a channel of the cordless fixed part belonging to each group for the purpose of find the channel where the cordless portable part, disposed between a first group and a second group, has attempted to transmit an outgoing call; means for fixing the frequency of the cordless parts at said channel where the cordless portable part has attempted to transmit the outgoing call and for comparing a received field strength with a predetermined communication field strength; means for storing the received field strength if the received field strength is more than the communication field strength and a means for determining whether or not link-request data has been received during a given period of time; means for determining whether or not the received field strength is more than a predetermined near-far field strength if the link-request data has been received during the given period of time and for transmitting a link-grant to the cordless portable part which has attempted the outgoing call if the received field strength is more than the near-far field strength; means for comparing a received cordless portable part ID with a cordless portable part ID of link-request data which has been previously received and stored in a memory if the received field strength is less than the near-far field strength and for increasing a count in a corresponding counter when the received cordless portable part ID is equal to the cordless portable part ID of the link-request data; and means for comparing the increased count in the counter with a predetermined count and for transmitting a link-grant to the cordless portable part which has attempted the outgoing call when the increased count in the counter is more than the predetermined count.

Claim 7

A radio calling apparatus for removing near-far problem in a radio switching system grouping a plurality of cordless fixed parts distributed in various areas in to at least first and second groups and controls communication of the groups with a cordless portable part, said apparatus comprising: a scanner for scanning a channel of the cordless fixed part belonging to each group for the purpose of find the channel where the cordless portable part, disposed between a first group and a second group, has attempted to transmit an outgoing call; means for fixing the frequency of the cordless parts at said channel where the cordless portable part has attempted to transmit the outgoing call and for comparing a received field strength with a predetermined communication field strength; means for storing the received field strength if the received field strength is more than the communication field strength and a means for determining whether or not link-request data has been received during a given period of time; means for determining whether or not the received field strength is more than a predetermined near-far field strength if the link-request data has been received during the given period of time and for transmitting a link-grant to the cordless portable part which has attempted the outgoing call if the received field strength is more than the near-far field strength; means for comparing a received cordless portable part ID with a cordless portable part ID of link-request data which has been previously received and stored in a memory if the received field strength is less than the near-far field strength and for increasing a count in a corresponding counter when the received cordless portable part ID is equal to the cordless portable part ID of the link-request data; and means for comparing the increased count in the counter with a predetermined count and for transmitting a link-grant to the cordless portable part which has attempted the outgoing call when the increased count in the counter is more than the predetermined count.

Claim 8

A radio switching circuit, comprising: means for designating a plurality of cordless fixed parts distributed in various different geographical areas into a plurality of groups comprising a first group and a second group, and for controlling communications of said groups with a cordless portable part; means for scanning a channel for a cordless fixed part belonging to each group, and for finding a channel where the cordless portable part has attempted to transmit an outgoing call, while the cordless portable part is disposed between said first and the second groups; means for fixing a frequency of the cordless fixed parts at the channel where the cordless portable part has attempted to transmit said outgoing call and for comparing a received field strength with a predetermined communication field strength; means for storing said received strength and for determining whether link-request data has been received during a given period of time when said received field strength is more than said communication field strength; means for determining whether said received field strength is more than a predetermined near-far field strength when said link-request data has been received during a given period of time and, for transmitting a link-grant to the cordless portable part that has attempted said outgoing call when said received field strength is greater than said near-far field strength; means for comparing a received cordless portable part ID with a second cordless portable part ID for link-request data that has previously been received and stored in a memory when said received field strength is less than said near-far field strength, and for determining whether a time-out of a corresponding timer has occurred when said received cordless portable part ID is equal to said second cordless portable port ID of the link-request data; and means for transmitting a link-grant to the cordless portable part that has attempted the outgoing call when the time-out of the corresponding timer has occurred.

Claim 9

A radio switching circuit, comprising: means for designating a plurality of cordless fixed parts distributed in various different geographical areas into a plurality of groups comprising a first group and a second group, and for controlling communications of said groups with a cordless portable part; means for scanning a channel for a cordless fixed part belonging to each group, and for finding a channel where the cordless portable part has attempted to transmit an outgoing call, while the cordless portable part is disposed between said first and the second groups; means for fixing a frequency of the cordless fixed parts at the channel where the cordless portable part has attempted to transmit said outgoing call and for comparing a received field strength with a predetermined communication field strength; means for storing said received strength and for determining whether link-request data has been received during a given period of time when said received field strength is more than said communication field strength; means for determining whether said received field strength is more than a predetermined near-far field strength when said link-request data has been received during a given period of time and, for transmitting a link-grant to the cordless portable part that has attempted said outgoing call when said received field strength is greater than said near-far field strength; means for comparing a received cordless portable part ID with a second cordless portable part ID for link-request data that has previously been received and stored in a memory when said received field strength is less than said near-far field strength, and for determining whether a time-out of a corresponding timer has occurred when said received cordless portable part ID is equal to said second cordless portable port ID of the link-request data; and means for transmitting a link-grant to the cordless portable part that has attempted the outgoing call when the time-out of the corresponding timer has occurred.