Mobile communication system with cell-site switching for intra-cell handoff
First Claim
1. A cellular mobile communication system comprising:
- a mobile switching center comprising;
a plurality of high-to-low bit rate converters for providing high to low bit rate conversion on signals from a switched network to produce low bit rate signals;
multiplexer means for composing said low bit rate signals from the high-to-low bit rate converters into a multiplex of low bit rate signals and transmitting the multiplex of low bit rate signals over a first transmission medium;
demultiplexer means for decomposing a multiplex of low bit rate signals from a second transmission medium into low bit rate component signals;
a plurality of low-to-high bit rate converters for respectively providing low to high bit rate conversion on the low bit rate component signals from the demultiplexer means and supplying high bit rate signals to the switched network; and
a controller for receiving a call request from the network; and
a base station comprising;
a controller for receiving a call request from mobile units, the controllers of the mobile switching center and the base station cooperating with each other in response to each of the respectively received call requests to produce a first channel assignment signal and transmitting the first channel assignment signal to a said mobile unit;
a plurality of modulators for establishing a plurality of forward channels;
demultiplexer means for decomposing the multiplex of said low bit rate signals from said first transmission medium into low bit rate component signals and applying the low bit rate component signals to said modulators according to said first channel assignment signal;
a plurality of demodulators for establishing a plurality of reverse channels; and
multiplexer means for transmitting outputs of said demodulators as said multiplex of low bit rate signals over said second transmission medium to the mobile switching center,the controller of the base station being responsive to an intra-cell handoff request from the said mobile unit for cooperating with the controller of the mobile switching center to produce a second channel assignment signal and applying the second channel assignment signal to said demultiplexer means of the base station to cause a said low bit rate component signal from said first transmission medium to be applied to another one of said modulators, and transmitting said second channel assignment signal to the said mobile unit.
1 Assignment
0 Petitions
Accused Products
Abstract
In a TDMA cellular mobile communication system, incoming signals from the public switched network are converted by speech coder/data compressor units of a MTSO (mobile telephone switching office) to low-bit-rate signals and combined into a first TDM signal for transmission to a base station. The components of the first TDM signal are respectively routed according to a channel assignment signal and fed into desired modulators which are periodically activated according to the channel assignment signal to transmit signals on assigned channels to mobile units. Signals from the mobile units are received by demodulators at the base station and combined into a second TDM signal which is transmitted to the MTSO. The components of the second TDM signal are routed according to the channel assignment signal to appropriate speech decoder/data expander units for conversion to the original high-bit-rate signals for transmission to the network.
170 Citations
15 Claims
-
1. A cellular mobile communication system comprising:
-
a mobile switching center comprising; a plurality of high-to-low bit rate converters for providing high to low bit rate conversion on signals from a switched network to produce low bit rate signals; multiplexer means for composing said low bit rate signals from the high-to-low bit rate converters into a multiplex of low bit rate signals and transmitting the multiplex of low bit rate signals over a first transmission medium; demultiplexer means for decomposing a multiplex of low bit rate signals from a second transmission medium into low bit rate component signals; a plurality of low-to-high bit rate converters for respectively providing low to high bit rate conversion on the low bit rate component signals from the demultiplexer means and supplying high bit rate signals to the switched network; and a controller for receiving a call request from the network; and a base station comprising; a controller for receiving a call request from mobile units, the controllers of the mobile switching center and the base station cooperating with each other in response to each of the respectively received call requests to produce a first channel assignment signal and transmitting the first channel assignment signal to a said mobile unit; a plurality of modulators for establishing a plurality of forward channels; demultiplexer means for decomposing the multiplex of said low bit rate signals from said first transmission medium into low bit rate component signals and applying the low bit rate component signals to said modulators according to said first channel assignment signal; a plurality of demodulators for establishing a plurality of reverse channels; and multiplexer means for transmitting outputs of said demodulators as said multiplex of low bit rate signals over said second transmission medium to the mobile switching center, the controller of the base station being responsive to an intra-cell handoff request from the said mobile unit for cooperating with the controller of the mobile switching center to produce a second channel assignment signal and applying the second channel assignment signal to said demultiplexer means of the base station to cause a said low bit rate component signal from said first transmission medium to be applied to another one of said modulators, and transmitting said second channel assignment signal to the said mobile unit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
Specification