Integrated personal/cellular communications system architecture

• US 5,303,287 A
• Filed: 08/13/1992
• Issued: 04/12/1994
• Est. Priority Date: 08/13/1992
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Laborde, Enrique
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): BLUM, RUSSELL
• Application Number:
  US07/929,603
• Time in Patent Office: 607 Days
• Field of Search: 370/95.1, 370/95.3, 370/69.1, 370/124, 379/59, 379/60, 455/33.1, 455/33.2, 455/33.4
• US Class Current: 455/426.1
• CPC Class Codes: H04W 16/12 Fixed resource partitioning
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

An integrated PCN/DCN system architecture has a switching center, coupled to a public switched telephone network (PSTN), which selectively transfers signals between the PSTN and a digital cellular network (DCN) or a personal communications network (PCN) which is allocated a portion of the cellular communications band by a local cellular operator. Each PCN subnetwork of the PCN includes several microcells arranged in a multi-dimensional grid, and the allocated cellular channels are divided into sets assigned to columns of the grid. The allocated portion of the cellular spectrum is reused within each PCN subnetwork by assigning the same set to more than one of the columns so that different communications signals can be transferred over the same cellular channels.

Claims

1. A personal communications network, PCN, for use over allocated cellular communications channels, said PCN comprising a plurality of PCN subnetworks, each of said PCN subnetworks comprising:

a plurality of microcells arranged in a multi-dimensional grid, said grid defining at least rows and columns of said microcells, wherein the allocated cellular communications channels are divided into sets of said cellular channels and each of said columns of said grid is assigned one of said sets for internal spectral reuse;

a plurality of centralized channel units divided into groups, each of said columns corresponding to a respective group, and each of said channel units in said respective group including means for transmitting signals over the set of cellular channels assigned to the corresponding column; and

a downstream distributor for distributing said signals transmitted by said channel units in said respective group to personal communications units positioned within said corresponding column.

2. The personal communications network of claim 1, wherein each of said PCN subnetworks is spaced at least a minimum distance apart from other Pc subnetworks, said minimum distance being sufficient such that substantial interference between signals transferred over the same cellular channels within different PCN subnetworks does not occur, enabling inter-PCN subnetwork frequency reuse.

3. The personal communications network of claim 1, wherein the columns assigned the same set of cellular channels within a subnetwork are spaced at least a minimum distance apart, said minimum distance being sufficient such that substantial interference between signals transferred over the same cellular channels within said PCN subnetwork does not occur, enabling said internal frequency reuse.

4. The personal communications network, PCN, of claim 1, wherein each of said columns is assigned an exclusive downstream band of channels and wherein said downstream distributor comprises:

a cellular downstream converter for converting signals transmitted over said cellular channels by channel units of said respective group to corresponding channels in the downstream band assigned to said corresponding column; and

a plurality of radio ports, each of said radio ports being disposed within a respective microcell, wherein each of said radio ports includes;

a downstream receive interface including means for receiving signals converted by said cellular downstream converter to channels within the downstream band assigned to the column of said respective microcell, and

a downstream transmit port including a downstream cellular converter for converting signals received by said downstream receive interface to the corresponding cellular channels, and means for transmitting the downstream cellular converted signals to personal communications units over said corresponding cellular channels.

5. The personal communications network of claim 4, wherein each downstream band of channels comprises a band of frequency division multiplex, FDM, channels, and said cellular downstream converter comprises a frequency division multiplexer for converting signals transmitted over cellular channels by channel units in said respective group to corresponding FDM channels within the downstream band assigned to said corresponding column.

6. The personal communications network of claim 5, wherein each downstream band of FDM channels comprises a bandwidth equivalent to that of the total of each of the allocated cellular communications channels.

7. The personal communications network of claim 5, wherein said downstream distributor further comprises:

a plurality of downstream wideband transmission media, each of said downstream wideband transmission media commonly connecting the downstream receive interface of each radio port disposed in a respective row of said grid to said frequency division multiplexer such that signals converted by said frequency division multiplexer are conducted to each of said downstream receive interfaces in said grid.

8. The personal communications network of claim 7, wherein each of said downstream wideband transmission media comprises a coaxial cable.

9. The personal communications network of claim 4 further comprising:

an upstream distributor for distributing signals transmitted by personal communications units positioned within a respective column to channel units in the group to which said respective column corresponds, wherein signals transmitted over respective cellular channels by said personal communications units are distributed to channel units which transmit over said respective cellular channels.

10. The personal communications network of claim 9, wherein said upstream distributor further comprises:

means for distributing signals transmitted by personal communications units positioned within columns adjacent to said respective column to channel units in the group to which said respective column corresponds, wherein signals transmitted over respective cellular channels of the set assigned to said respective column by personal communications units within said columns adjacent to said respective column are distributed to channels units which transmit over said respective channels.

11. The personal communications network of claim 9, wherein each of said columns is assigned an exclusive upstream band of channels, and wherein said upstream distributor further comprises:

upstream receive ports, each of said upstream receive ports being associated with a radio port of said respective column, including means for receiving signals transmitted over cellular channels by personal communications units, and a cellular upstream converter for converting the signals received from said personal communications units to corresponding channels in the upstream band assigned to said respective column;

upstream transmit interfaces, each of said upstream transmit interfaces being associated with a radio port of said respective column, for transmitting the signals converted by the associated cellular upstream converter over the corresponding channels in the upstream band assigned to said respective column; and

an upstream cellular converter for converting signals transmitted by the upstream transmit interfaces of radio ports of said respective column and of columns adjacent to said respective column to the corresponding cellular channels, and for transmitting the upstream-cellular converted signals to channel units in the group to which said respective column corresponds,

wherein signals transmitted over respective cellular channels of the set assigned to said respective column by personal communications units within said respective column and said columns adjacent to said respective column are transmitted to channels units which transmit over said respective channels.

12. The personal communications network of claim 11, wherein each downstream band of channels and each upstream band of channels comprises a band of frequency division multiplex, FDM, channels, said cellular downstream converter comprising a frequency division multiplexer for converting signals transmitted over cellular channels by channel units in said respective group to corresponding FDM channels within the band assigned to the corresponding column, and said upstream cellular converter comprising a frequency division demultiplexer for converting said signals transmitted over FDM channels by said upstream transmit interfaces of said respective column and of said columns adjacent to said respective column to the corresponding cellular channels within the set assigned to said respective column.

13. The personal communications network of claim 12, wherein each upstream band and each downstream band of FDM channels comprises a bandwidth equivalent to that of the total of each of the allocated cellular communications channels.

14. The personal communications network of claim 12, wherein said downstream distributor further comprises

a plurality of downstream wideband transmission media, each of said downstream wideband transmission media commonly connecting the downstream receive interfaces of each radio port disposed in a respective row of said grid to said frequency division multiplexer such that signals converted by said frequency division multiplexer are conducted to each of said downstream receive interfaces in said grid, and wherein said upstream distributor further comprises a plurality of upstream wideband transmission media commonly connecting the upstream transmit interfaces of each radio port disposed in a respective row of said grid to said frequency division demultiplexer.

15. The personal communications network of claim 14, wherein each of said downstream wideband transmission media and each of said upstream wideband transmission media comprises a coaxial cable.

16. The personal communications network of claim 15, wherein said frequency division multiplexer comprises a plurality of cable multiplexers, each of said cable multiplexers being connected to a respective one of the downstream cables, and wherein each of said channel units includes a passive splitter for splitting the signals transmitted by each channel unit into a plurality of paths and for connecting each of said paths to a respective cable multiplexer such that the signals transmitted by each of said channel units in a respective group are transmitted in simulcast by the downstream transmit ports of the radio ports in the corresponding column.

17. The personal communications network of claim 12, wherein each of said channel units includes a multisite diversity controller for selecting the strongest of the signals received from said frequency division demultiplexer which correspond to a respective communications and for transmitting the selected signal to a base station controller, said base station controller including means for transmitting the selected signal to a switching center and means for transmitting signals from said switching center to selected channel units.

18. The personal communications network of claim 17, wherein each of said channel units includes means for indicating the column in said grid from which said selected signals was received on the basis of the upstream FDM channel over which said selected signal was transmitted, said base station controller including hand-off means for transmitting signals from said switching center which correspond to said respective communications to a channel unit in the group to which the column from which said selected signal corresponds.

19. The personal communications network of claim 17, wherein said switching center includes means for transferring signals between said base station controller and a public switched telephone network, and wherein said base station controller includes means for transferring signals between said channel units and a private branch exchange network.

20. The personal communications network of claim 8, wherein each of said channel units includes means for transmitting signals over time slots of said cellular channels, each of said time slots being assigned to a respective personal communications unit.

21. A personal communications network, PCN, for use over allocated cellular communications channels, said PCN comprising a plurality of PCN subnetworks, each of said PCN subnetworks comprising:

a plurality of microcells arranged in a multi-dimensional grid, said grid defining at least rows and columns of said microcells, wherein cellular communications channels allocated to the subnetwork are divided into sets of said channels and wherein each of said columns of said grid is assigned one of said sets;

a multisite diversity controller for receiving signals transmitted by personal communications units positioned within a respective column but received in other columns and comparing the quality of the received signals; and

a hand-off controller for reassigning personal communications units from one column to another in response to said comparison by said multisite diversity controller by changing the channels to which corresponding microcells are assigned.

22. The personal communications network of claim 21, further comprising:

an upstream distributor for distributing signals transmitted by personal communications units positioned within a respective column to channel units in the group to which said respective column corresponds, wherein signal transmitted over respective cellular channels by said personal communications units are distributed to channel units which transmit over said respective cellular channels;

said upstream distributor further comprising means for distributing signals transmitted by personal communications units positioned within columns adjacent to said respective column to channel units in the group to which said respective cellular channels of the set assigned to said respective column by personal communications units within said columns adjacent to said respective column are distributed to channels units which transmit over said respective channels; and

wherein said multisite diversity controller compares the quality of the signals of adjacent columns by said channel units.

23. The personal communications network of claim 22, wherein each of said columns is assigned an exclusive upstream band of channels, and wherein said upstream distributor comprises:

upstream receive ports, each of said upstream receive ports being associated with a radio port of said respective column, including means for receiving signals transmitted over cellular channels by personal communications units, and a cellular upstream converter for converting the signals received from said personal communications units to corresponding channels in the upstream band assigned to said respective column;

upstream transmit interfaces, each of said upstream transmit interfaces being associated with a radio port of said respective column, for transmitting the signals converted by the associated cellular upstream converted over the corresponding channels in the upstream band assigned to said respective column; and

an upstream cellular converter for converting signals transmitted by the upstream transmit interfaces of radio ports of said respective column and of columns adjacent to said respective column to the corresponding cellular channels, and for transmitting the upstream-cellular converted signals to channel units in the group to which said respective column corresponds,

wherein signals transmitted over respective cellular channels of the set assigned to said respective column bu personal communications units within said respective column and said columns adjacent to said respective column are transmitted to channels units which transmit over said respective channels.

24. The personal communications network of claim 23 wherein each upstream band of channels comprises a band of frequency division multiplex, FDM, channels, said upstream cellular converter comprising a frequency division demultiplexer for converting said signals transmitted over FDM channels by said upstream transmit interfaces of said respective column and of said columns adjacent to said respective column to the corresponding cellular channels within the set assigned to said respective column and wherein said multisite diversity controller compares the quality of received signals by comparing the quality of the signals received from said demultiplexer which correspond to a respective communication.

25. The personal communications network of claim 21 wherein the multisite diversity controller selected the strongest of said received signals for transmission to a communications switching center of the personal communications network,

26. A personal communications network, PCN, for use over allocated cellular communications channels, said PCN comprising a plurality of PCN subnetworks, each of said PCN subnetworks comprising:

a plurality of microcells arranged in a multi-dimensional grid, said grid defining at least rows and columns of said microcells, wherein the allocated cellular channels are divided into sets of said cellular channels and each of said columns of said grid is assigned one of said sets for internal spectral reuse;

an upstream distributor for distributing signals transmitted by personal communications units positioned within a respective column to channel units in the group to which said respective column corresponds, wherein signals transmitted over respective cellular channels by said personal communications units are distributed to channel units which transmit over said respective cellular channels;

said upstream distributor further comprising means for distributing signals transmitted by personal communications units positioned within columns adjacent to said respective column to channel units in the group to which said respective column corresponds, wherein signals transmitted over respective cellular channels of the set assigned to said respective column by personal communications units within said columns adjacent to said respective column are distributed to channels units which transmit over said respective channels; and

a multisite diversity controller for selecting the strongest of said transmitted signals of a respective cellular channel for transmission to a communications switching center of the personal communications network.

27. The personal communications network of claim 26, wherein each of said columns is assigned an exclusive upstream band of channels, and wherein said upstream distributor comprises:

upstream receive ports, each of said upstream receive ports being associated with a radio port of said respective column, including means for receiving signals transmitted over cellular channels by personal communications units, and a cellular upstream converter for converting the signals received from said personal communications units to corresponding channels in the upstream band assigned to said respective column;

upstream transmit interfaces, each of said upstream transmit interfaces being associated with a radio port of said respective column, for transmitting the signals converted by the associated cellular upstream converter over the corresponding channels in the upstream and assigned to said respective column; and

an upstream cellular converter for converting signals transmitted by the upstream transmit interfaces of radio ports of said respective column and of columns adjacent to said respective column to the corresponding cellular channels, and for transmitting the upstream-cellular converted signals to channel units in the group to which said respective column corresponds,

wherein signals transmitted over respective cellular channels of the set assigned to said respective column by personal communications units within said respective column and said columns adjacent to said respective column are transmitted to channels units which transmit over said respective channels.

28. The personal communications network of claim 27 wherein each upstream band of channels comprises a and of frequency division multiplex, FDM, channels, said upstream cellular converter comprising a frequency division demultiplexer for converting said signals transmitted over FDM channels by said upstream transmit interfaces of said respective column and of said columns adjacent to said respective column to the corresponding cellular channels within the set assigned to said respective column and wherein said multisite diversity controller selects from among the signals received from said demultiplexer which correspond to a respective communication.