Spread-spectrum frequency-hopping radiotelephone system

Claim 2

A multiple access communications system in which a set of N carrier frequencies are reused in a plurality of adjacent communications sites of said communications system to provide greater than N minimally cross correlated frequency hopping communications channels in said system, said system comprising: means for defining a first set of said minimally cross correlated frequency hopping communications channels associated with a first of said plurality of adjacent communications sites in which no two of said channels in said first set of said minimally cross correlated frequency hopping communications channels employ the same one of said N carrier frequencies at the same time; and means for defining a second set of said minimally cross correlated frequency hopping communications channels associated with a second of said plurality of adjacent communications sites in which no two of said channels in said second set of said minimally cross correlated frequency hopping communications channels employ the same one of said N carrier frequencies at the same time.

Claim 3

The multiple access communications system as defined in Claims 1 further comprising: means for defining a third set of said minimally cross correlated frequency hopping communications channels associated with a third of said plurality of adjacent communications sites in which no two of said channels in said third set of said minimally cross correlated frequency hopping communications channels employ the same one of said N carrier frequencies at the same time.

Claim 4

The multiple access communications system as defined in Claims 1 or 2 in which: said second set of said minimally cross correlated channels is further defined so that no one of said channels in said second set of said minimally cross correlated frequency hopping communications channels employ the same one of said N carrier frequencies at the same time as more than a predetermined number of said channels in said first set of said minimally cross correlated frequency hopping communications channels; where said predetermined number is the minimum number of channels possible.

Claim 5

The multiple access communications system as defined in Claim 3 in which: said third set of said minimally cross correlated channels is further defined so that no one of said channels in said third set of said minimally cross correlated frequency hopping communications channels employ the same one of said N carrier frequencies at the same time as more than a predetermined number of said channels in said first set of said minimally cross correlated frequency hopping communications channels and also do not employ the same one of said N carrier frequencies at the same time as more than said predetermined number of said channels in said second set of said minimally cross correlated frequency hopping communications channels.

Claim 6

The multiple access communications system as defined in any of the preceding claims in which the predetermined number is one.

Claim 7

The multiple access communications system as defined in any of claims 3-5, said system also including means for selectively encoding digital information signals on ones of said minimally cross correlated frequency hopping communications channels such that there is a redundant relationship between channel bits; error correcting means for setting said relationship; and decoder means for utilizing said relationship for error correction.

Claim 8

The multiple access communications system as defined in Claim 6 also including decoding means for decoding said digital information signals which includes the use of soft decision making and side information.

Claim 9

The multiple access communications system as defined in claims 1-7, said system further comprising: voice activity detection means for measuring signal activity levels representative of subscriber voice activity on an assigned channel to generate a channel voice activity signal; and means responsive to said channel voice activity signal for selectively allocating channels to subscribers.

Claim 10

The multiple access communications system as defined in any of the preceding claims in which said second set of said minimally cross correlated frequency hopping communications channels is further defined as a first decimated transformation of each of said minimally cross correlated frequency hopping communications channels in said first set.

Claim 11

The multiple access communications system as defined in Claim 9 in which said third set of said minimally cross correlated frequency hopping communications channels is further defined as a second decimated transformation of each of sad minimally cross correlated frequency hopping communications channels in said first set.

Claim 12

The multiple access communications system as defined in Claim 9 in which each of said minimally cross correlated frequency hopping communications channels in said first set is defined by a unique sequence of said frequencies and said first decimating transformation is performed on each of said minimally cross correlated frequency hopping communications channels in said first set by selecting frequencies from each of said minimally cross correlated frequency hopping communications channels in said first set in their sequential order skipping a first decimation number of frequencies in said sequence and repeating this process on the remaining frequencies in said sequence of each channel in their remaining order until all of the frequencies in each channel are used to define said second set of minimally cross correlated frequency hopping communications channels.

Claim 13

The multiple access communications system as defined in Claim 10 in which each of said minimally cross correlated frequency hopping communications channels in sad first set is defined by a unique sequence of said frequencies and said first decimating transformation is performed on each of said minimally cross correlated frequency hopping communications channels in said first set by selecting frequencies from each of said minimally cross correlated frequency hopping communications channels in said first set in their sequential order skipping a first decimation number of frequencies in said sequence and repeating this process on the remaining frequencies in said sequence of each channel in their remaining order until all of the frequencies in each channel are used to define said second set of minimally cross correlated frequency hopping communications channels and said second decimating transformation is performed on each of said minimally cross correlated frequency hopping communications channels in said first set by selecting frequencies from each of said minimally cross correlated frequency hopping communications channels in said first set in their sequential order skipping a second decimation number of frequencies in said sequence and repeating this process on the remaining frequencies in said sequence of each channel in their remaining order until all of the frequencies in each channel are used to define said third set of minimally cross correlated frequency hopping communications channels, wherein said first and second decimation numbers are different and each is less than the minimum factor of N.

Claim 14

The multiple access communications system as defined in any of the preceding claims, said system further comprising: means for performing a conference call between a plurality of subscribers in a site by causing each of said subscribers to employ the same channel.

Claim 15

The multiple access communications system as defined in any of the preceding claims, said system further comprising: an electronically controlled antenna; means responsive to a control signal for controlling said antenna to provide a first antenna radiation pattern for defining said first of said plurality of adjacent communications sites; means responsive to a control signal for controlling said antenna to provide a second antenna radiation pattern which overlaps with said first antenna radiation pattern at a boundary for defining said second of said plurality of adjacent communications sites; and means responsive to the number of said system subscribers using each of said first and second of said plurality of adjacent communications sites for affecting said control signal to move said boundary.

Claim 16

The multiple access communications system as defined in any of the preceding claims, said system further comprising: means for defining a first micro-site within said first of said plurality of adjacent communications sites; said first micro-site reusing said N frequencies; said micro-site being characterized by an average power of no greater than ten percent of that of said plurality of adjacent communications sites.

Claim 17

The multiple access communications system as set forth in Claim 15 further comprising: a base station: and in which a plurality of subscribers use said multiple access communications system by communicating through said base station using an uplink communications channel and a downlink communications channel; and means located in said base station for directly connecting two subscribers using said system if they are both in said micro-site by causing one of said two subscribers to communicate uplink with a first downlink channel and downlink with an first uplink channel and causing said other of said two subscribers to communicate uplink on said first uplink channel and down link on said first downlink channel.

Claim 18

A multiple access communications system in which a set of N frequencies are reused in a plurality of adjacent communications sites of said communications system to provide greater than N communications channels in said system for the use of system subscribers, said system comprising: an electronically controlled antenna; means responsive to a control signal for controlling said antenna to provide a first antenna radiation pattern for defining a first of said plurality of adjacent communications sites; means responsive to a control signal for controlling said antenna to provide a second antenna radiation pattern which overlaps with said first antenna radiation pattern at a boundary for defining a second of said plurality of adjacent communications sites; and means responsive to the number of said system subscribers using each of said first and second of said plurality of adjacent communications sites for affecting said control signal to move said boundary.

Claim 19

A multiple access communications system in which a set of N frequencies are reused in a plurality of adjacent communications sites of said communications system to provide greater than N communications channels in said system for the use of system subscribers, said system comprising: an electronically controlled antenna; means responsive to a control signal for controlling said antenna to provide a first antenna radiation pattern for defining a first of said plurality of adjacent communications sites; means responsive to a control signal for controlling said antenna to provide a second antenna radiation pattern which overlaps with said first antenna radiation pattern at a boundary for defining a second of said plurality of adjacent communications sites; and means responsive to the number of said system subscribers using each of said first and second of said plurality of adjacent communications sites for affecting said control signal to move said boundary.

Claim 20

A multiple access communications system in which a set of N frequencies are reused in a plurality of adjacent communications sites of said communications system to provide greater than N communications channels in said system, said system comprising: a first antenna having a first antenna radiation pattern for defining a first of said plurality of adjacent communications sites; a second antenna having a second antenna radiation pattern which overlaps with said first antenna radiation pattern at a boundary for defining a second of said plurality of adjacent communications sites; and a third antenna having a third antenna radiation pattern for defining a first micro-site within said first of said plurality of adjacent communications sites; said first micro-site reusing said N frequencies and said third antenna radiation pattern being characterized by a mean power of no greater than ten percent that of said first antenna radiation pattern.

Claim 21

A multiple access communications system in which a set of N frequencies are reused in a plurality of adjacent communications sites of said communications system to provide greater than N communications channels in said system, said system comprising: a first antenna having a first antenna radiation pattern for defining a first of said plurality of adjacent communications sites; a second antenna having a second antenna radiation pattern which overlaps with said first antenna radiation pattern at a boundary for defining a second of said plurality of adjacent communications sites; and a third antenna having a third antenna radiation pattern for defining a first micro-site within said first of said plurality of adjacent communications sites; said first micro-site reusing said N frequencies and said third antenna radiation pattern being characterized by a mean power of no greater than ten percent that of said first antenna radiation pattern.

Claim 22

The multiple access communications system as set forth in Claim 18 further comprising: a base station; and in which a plurality of subscribers use said multiple access communications system by communicating through said base station using an uplink communications channel and a downlink communications channel; and means located in said base station for directly connecting two subscribers using said system if they are both in said third antenna radiation pattern by causing one of said two subscribers to communicate uplink with a first downlink channel and downlink with an first uplink channel and causing said other of said two subscribers to communicate uplink on said first uplink channel and down link on said first downlink channel.