SSB communication system with FM data capability

Claim 2

A radio communication system having a primary station and at least one remote station, said primary and remote stations adapted to operate on a plurality of radio frequency channels, said radio communication system comprising: said primary station including; means for transmitting voice messages via a first type of modulation within a first channel of said plurality of channels, said first channel having a predetermined channel bandwidth; and means for transmitting a first set of data messages via a second type of modulation within a second channel of said plurality of channels, said first set of data messages including receiver control information, said second channel having a predetermined channel bandwidth being no wider than said first channel bandwidth; and said remote station including; means for alternatively receiving one of either: (a) said voice messages; and (b) said first set of data messages; and means for automatically controlling said receiving means such that said voice messages are received from said first channel in response to said receiver control information derived from said first set of data messages received from said second channel.

Claim 3

The radio communication system according to claim 1, wherein said first type of modulation is amplitude modulation and wherein said second type of modulation is angle modulation.

Claim 4

The radio communication system according to claim 2, wherein said amplitude modulation is single sideband (SSB) amplitude modulation (AM).

Claim 5

The radio communication system according to claim 3, wherein said first radio channel includes an audio subcarrier located outside the voice frequency band.

Claim 6

The radio communication system according to claim 4, wherein said primary station further includes means for modulating a second set of data messages on said first channel audio subcarrier within said first channel bandwidth.

Claim 7

The radio communication system according to claim 5, wherein said remote station controlling means further includes means for automatically controlling said receiving means such that said first set of data messages is received from said second channel in response to information derived from said second set of data messages received from said first channel.

Claim 8

The radio communication system according to claim 3, wherein said SSB-AM includes a reduced pilot carrier.

Claim 9

The radio communication system according to claim 2, wherein said angle modulation is narrowband frequency modulation (FM).

Claim 10

The radio communication system according to claim 1, wherein said receiving means includes means for selectively deriving an automatic frequency control (AFC) signal from one of said first and second types of modulation.

Claim 11

The radio communication system according to claim 1, wherein said first channel bandwidth is less than or equal to 7.5 kHz.

Claim 12

The radio communication system according to claim 1, wherein said first and second channels comprise any two of said plurality of radio frequency channels.

Claim 13

The radio communication system according to claim 1, wherein said first and second channels occupy a single radio frequency spectrum at different times.

Claim 14

A radio communication system having a base station transceiver and a plurality of remote station transceivers, each of said base and remote station transceivers adapted to transmit and receive voice and data signals over any one of a plurality of communications channels, said radio communication system comprising: said base station transceiver including; means for transmitting a given frequency band of voice signals via single sideband (SSB) amplitude modulation (AM) within a first channel of said plurality of channels, said first channel having a predetermined channel bandwidth, said SSB-AM including an audio subcarrier located outside said voice band; means for modulating low speed data signals on said first channel audio subcarrier within said first channel bandwidth; means for transmitting high speed data signals via narrowband frequency modulation (FM) within a second channel of said plurality of channels, said second channel having a predetermined channel bandwidth being no wider than said first channel bandwidth; and each of said remote station transceivers including; means for selectively receiving one of either: (a) said SSB-AM voice signals; and (b) said narrowband FM high speed data signals; means for decoding information contained in said received high speed data signals to provide a first receiver control signal; and means responsive to said first receiver control signal for automatically selecting one of said plurality of channels to be received by said remote station receiving means.

Claim 15

A radio communication system having a base station transceiver and a plurality of remote station transceivers, each of said base and remote station transceivers adapted to transmit and receive voice and data signals over any one of a plurality of communications channels, said radio communication system comprising: said base station transceiver including; means for transmitting a given frequency band of voice signals via single sideband (SSB) amplitude modulation (AM) within a first channel of said plurality of channels, said first channel having a predetermined channel bandwidth, said SSB-AM including an audio subcarrier located outside said voice band; means for modulating low speed data signals on said first channel audio subcarrier within said first channel bandwidth; means for transmitting high speed data signals via narrowband frequency modulation (FM) within a second channel of said plurality of channels, said second channel having a predetermined channel bandwidth being no wider than said first channel bandwidth; and each of said remote station transceivers including; means for selectively receiving one of either: (a) said SSB-AM voice signals; and (b) said narrowband FM high speed data signals; means for decoding information contained in said received high speed data signals to provide a first receiver control signal; and means responsive to said first receiver control signal for automatically selecting one of said plurality of channels to be received by said remote station receiving means.

Claim 16

The radio communication system according to claim 13, wherein said receiving means includes means for receiving said low speed data modulation with said SSB-AM voice signals from said first channel.

Claim 17

The radio communication system according to claim 14, wherein said remote station transceivers include means for deriving information from said received low speed data signal to provide a second receiver control signal.

Claim 18

The radio communication system according to claim 15, wherein said remote station transceivers further include means responsive to said second receiver control signal for automatically selecting said second channel containing said high speed data signals to be received by said remote station receiving means.

Claim 19

The radio communication system according to claim 13, wherein said SSB-AM includes a reduced pilot carrier.

Claim 20

The radio communication system according to claim 17, wherein the amplitude of said pilot carrier is approximately 16 dB below peak envelope power.

Claim 21

The radio communication system according to claim 13, wherein said second channel high speed data is transmitted without a pilot carrier.

Claim 22

The radio communication system according to claim 19, wherein said high speed data signals are transmitted at full peak envelope power.

Claim 23

The radio communication system according to claim 13, wherein said receiving means includes means for selectively deriving an automatic frequency control (AFC) signal from one of said SSB-AM and narrowband FM types of modulation.

Claim 24

The radio communication system according to claim 21, wherein said AFC means tracks said SSB-AM reduced pilot carrier whenever said receiver means receives said first channel.

Claim 25

The radio communication system according to claim 21, wherein said AFC means tracks the approximate center frequency of said narrowband FM high speed data signals whenever said receiving means receives said second channel.

Claim 26

The radio communication system according to claim 13, wherein the amplitude of said audio subcarrier is approximately 17.5 dB below peak envelope power.

Claim 27

The radio communication system according to claim 13, wherein the peak amplitude of said voice signals is approximately 3.0 dB below peak envelope power.

Claim 28

The radio communication system according to claim 13, wherein said audio subcarrier is located at approximately 3.46 kHz above the lower edge frequency of said first channel.

Claim 29

The radio communication system according to claim 13, wherein said first channel low speed data is NRZ FSK data modulation at approximately 150 bps.

Claim 30

The radio communication system according to claim 13, wherein the peak frequency deviation of said low speed data modulation is approximately 80 Hz.

Claim 31

The radio communication system according to claim 13, wherein said high speed data is centered at approximately 1.9 kHz above the lower edge frequency of said second channel.

Claim 32

The radio communication system according to claim 13, wherein said second channel high speed data is NRZ FSK data modulation at approximately 2400 bps.

Claim 33

The radio communication system according to claim 13, wherein the frequency deviation of said high speed data modulation is approximately 800 Hz.

Claim 34

The radio communication system according to claim 13, wherein said first channel bandwidth is less than or equal to 7.5 kHz.

Claim 35

The radio communication system according to claim 13, wherein each of said plurality of communications channels have equal bandwidths.

Claim 36

The radio communication system according to claim 13, wherein said first and second channels occupy a single radio frequency spectrum at different times.

Claim 39

The method of communicating according to claim 35, wherein said SSB-AM includes a reduced pilot carrier.

Claim 40

The method of communicating according to claim 36, further including the step of providing automatic frequency control (AFC) in said remote station by selectively deriving an AFC signal from one of said SSB-AM and narrowband FM types of modulation.

Claim 41

The method of communicating according to claim 37, wherein said AFC signal tracks said SSB-AM reduced pilot carrier whenever said remote station receives said first channel.

Claim 42

The method of communicating according to claim 37, wherein said AFC signal tracks the approximate center frequency of said narrowband FM high speed data signals whenever said remote station receives said second channel.

Claim 43

The method of communicating according to claim 35, further including the steps of: transmitting from said primary station an audio subcarrier located outside the voice frequency band within said first channel bandwidth; modulating a second set of data messages on said audio subcarrier within said first channel bandwidth; receiving in said remote station said second set of data messages from said first channel; deriving information from said second set of data messages to provide a second receiver control signal; and automatically controlling said remote station such that said first set of data messages is received from said second channel in response to said second receiver control signal.

Claim 44

The method of communicating according to claim 35, wherein said first and second channels occupy a single radio frequency spectrum at different times.

Claim 47

The method of receiving according to claim 42, wherein said SSB-AM includes a reduced pilot carrier.

Claim 48

The method of receiving according to claim 43, further including the step of providing automatic frequency control (AFC) in said remote station by selectively deriving an AFC signal from one of said SSB-AM and narrowband FM types of modulation.

Claim 49

The method of receiving according to claim 44, wherein said AFC signal tracks said SSB-AM reduced pilot carrier whenever said remote station receives said first channel.

Claim 50

The method of receiving according to claim 44, wherein said AFC signal tracks the approximate center frequency of said narrowband FM high speed data signals whenever said remote station receives said second channel.

Claim 51

The method of receiving according to claim 42, further including the steps of: receiving in said remote station a second set of data messages modulated on an audio subcarrier located outside the voice frequency band within said first channel bandwidth; deriving information from said second set of data messages to provide a second receiver control signal; and automatically controlling said remote station such that said first set of data messages is received from said second channel in response to said second receiver control signal.

Claim 52

The method of receiving according to claim 42, wherein said first and second channels occupy a single radio frequency spectrum at different times.

Claim 55

The method of transmission according to claim 49, wherein said first set of data signals are transmitted from said primary station via narrowband frequency modulation.

Claim 56

The method of transmission according to claim 49, wherein said first and second channels occupy a single radio frequency spectrum at different times.