RADIO DEVICES AND COMMUNICATIONS

• US 20100148931A1
• Filed: 12/12/2008
• Published: 06/17/2010
• Est. Priority Date: 12/12/2008
• Status: Abandoned Application

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Maguire, Yael Gregory, Viswanathan, Arun, Pappu, Ravikanth Srinivasa, Fiegel, Brian, Schoner, Bernd
• Application Number:
  US12/333,988
• Publication Number:
  US 20100148931A1
• Time in Patent Office: Days
• US Class Current: 340/10.200
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: G06Q 10/0833 Tracking
• CPC Class Codes: H04Q 2213/13003 Constructional details of switching devices

Abstract

Each of multiple radio devices in a region (e.g., a zone) receives time reference information for synchronizing themselves amongst each other. For example, based on the timing reference information, each radio device in a region synchronizes itself with respect to a common time reference, enabling communications according to shared access schedule (e.g., a time slotted access schedule). Each of the radio devices schedules communications to one or more target devices (e.g., RFID tags) in a monitored region based at least in part according to the shared access schedule. For example, each of multiple transmitters of the tag readers are assigned one or more time slots of the shared access schedule in which they are permitted to communicate in the monitored region.

Claims

1. A method of operating a given wireless transceiver device that communicates with multiple wireless identification tags in a monitored region, the method comprising:

receiving time reference information;

based on the timing reference information, synchronizing the wireless transceiver device with multiple other wireless transceiver devices that communicate in the monitored region; and

scheduling communications from the given wireless transceiver device to at least one of the multiple wireless identification tags in the monitored region.

2. A method as in claim 1, wherein receiving time reference information occurs in response to:

initiating communications over a respective network to retrieve the time reference information from a server for purposes of synchronizing wireless transmissions from the given wireless transceiver device with respect to wireless transmissions by the multiple other wireless transceiver devices that also communicate in the monitored region.

3. A method as in claim 1, wherein receiving time reference information includes receiving the time reference information from a respective GPS (Global Positioning System) device, the method further comprising:

communicating with the GPS device to obtain respective location information for purposes of learning a respective whereabouts of the given wireless transceiver device.

4. A method as in claim 1, wherein scheduling communications includes selecting a particular one of multiple wireless channels or frequency bands as a carrier medium on which to communicate from the given wireless transceiver device to at least one of the wireless identification tags in the monitored region.

5. A method as in claim 1, wherein scheduling communications from the given wireless transceiver device includes:

scheduling the given wireless transceiver device to initiate wireless communications on a respective channel in the monitored region during a respective transmit duration in which at least one of the other wireless transceiver devices is also scheduled to transmit on the respective channel.

6. A method as in claim 5, wherein scheduling the given wireless transceiver device to initiate wireless communications on the respective channel includes:

subdividing the transmit duration to include a first part and a second part;

scheduling the given wireless transceiver device to communicate on the respective channel during the first part of the time duration exclusive of the other wireless transceiver devices; and

disabling the given wireless transceiver device from communicating during the second part of the transmit duration which is apportioned for use by at least one of the other wireless transceiver devices to communicate in the monitored region.

7. A method as in claim 1 further comprising:

scheduling a first listen time duration for the given wireless transceiver device to listen for wireless transmissions in the monitored region from sources other than the multiple other wireless transceiver devices, the first time duration being substantially a same time as when the multiple other wireless transceiver devices also listen for wireless transmissions in the monitored region;

after the first listen time duration, scheduling a second listen time of a random duration for the given wireless transceiver device to listen for wireless transmissions by the multiple other wireless transceiver devices; and

scheduling the given wireless transceiver device to communicate in the monitored region after the second listen time.

8. A method as in claim 1, wherein synchronizing the given wireless transceiver device causes the given wireless transceiver device to become part of a first zone of multiple zones of synchronized wireless transceiver devices, the first zone including the given wireless transceiver device and the multiple other wireless transceiver devices, a second zone of the multiple zones including a corresponding remote group of synchronized wireless transceiver devices i) that operate off of a unique master clock with respect to a corresponding master clock used to synchronize the wireless transceiver devices in the first zone and ii) that do not interfere with communications initiated by the wireless transceiver devices in the first zone.

9. A method as in claim 8 further comprising:

scheduling the given wireless transceiver device in the first zone to initiate wireless transmissions while i) each of the other multiple wireless transceiver devices are disabled from transmitting, and ii) each wireless transceiver device in the second zone attempts to detect the wireless transmissions from the given wireless transceiver device transmitting in the first zone.

10. A method as in claim 1 further comprising:

operating the given wireless transceiver device amongst at least one wireless transceiver device that communicates with the wireless identification tags in the monitored region but is not synchronized as part of a respective zone of synchronized wireless transceiver devices including the given wireless transceiver device and the multiple other wireless transceiver devices.

11. A method as in claim 1, wherein scheduling communications from the given wireless transceiver device includes:

utilizing the timing reference information to;

schedule a first time duration in which the given wireless transceiver device transmits an unmodulated wireless carrier signal to provide power to at least one of the multiple wireless identification tags in the monitored region;

schedule a second time duration in which the given wireless transceiver device transmits a modulated wireless carrier signal to communicate a message to the at least one wireless identification tag; and

schedule a third time duration in which the given wireless transceiver device simultaneously i) transmits the unmodulated wireless carrier signal to provide power to the at least one of the multiple wireless identification tag in the monitored region, and ii) receives a modulated signal from the wireless transceiver device to receive a response from the at least one wireless identification tag.

12. A method as in claim 1, wherein receiving time reference information includes receiving the time reference information in a form of a wireless synchronization signal.

13. A method as in claim 1, wherein more than one wireless transceiver device operates in a given region receiving different modes of time reference information synchronized to the same time reference information

14. A method as in claim 1, wherein multiple types of wireless transceivers are assigned different time slots such that only wireless transceivers of the same type transmit a during a given time slot.

15. A method as in claim 14, wherein a first type of wireless devices is assigned to communicate in a first time slot of a time slotted access schedule shared by the wireless transceiver device and the other wireless transceiver devices that communicate in the monitored region;

and

wherein a second type of wireless devices is assigned to communicate in a second time slot of a time slotted access schedule.

16. A method as in claim 15, wherein the first type of wireless transceiver devices includes transmitters that make different spectral use of wireless channels than those in the second type of wireless transceiver devices.

17. A method as in claim 16, wherein the first type of wireless transceiver devices includes wireless transmitters that transmit at different respective power levels and use different communication protocols than wireless transmitters associated with the second type of wireless transceiver devices.

18. A method comprising:

receiving synchronization information;

utilizing the synchronization information to synchronize a given RFID tag reader with a set of other RFID tag readers; and

initiating communications from at least one antenna associated with the given RFID tag reader in assigned time slots.

19. A method as in claim 18 further comprising:

prior to communicating in a region, monitoring the region for a presence of RF energy.

20. A method as in claim 18 further comprising:

receiving antenna assignment information indicating in which of multiple possible time slots that corresponding antennas associated with the given RFID tag reader are permitted to transmit RF energy for communicating with RFID tags in a monitored region; and

wherein initiating the communications from the at least one antenna associated with the given RFID tag reader includes initiating communications from at least one of the corresponding antennas in a permitted time slot as specified by the antenna assignment information to communicate with the RFID tags.

21. A method as in claim 20, wherein initiating the communications includes communicating in the permitted time slot based on a communication schedule associated with the given RFID tag reader.

22. A method as in claim 18 further comprising:

receiving antenna assignment information from a centralized location that generates rules indicating in which of multiple time slots directional antennas associated with the given RFID tag reader and the set of other RFID tag readers are permitted to communicate with respective RFID tags.

23. A method as in claim 18, wherein initiating communications from the at least one antenna associated with the given RFID tag reader in assigned time slots includes:

communicating in a monitored region via a first directional antenna of the given RFID tag reader during a first time slot; and

communicating in the monitored region via a second directional antenna of the given RFID tag reader during a second time slot.

24. A method as in claim 18, wherein initiating communications from the at least one antenna associated with the given RFID tag reader in assigned time slots includes:

based on receipt of antenna assignment information, scheduling autonomous communications from a first directional antenna of the given RID tag reader during a first time slot in which multiple non-interfering antennas associated with the set of other tag readers are also permitted to communicate in the first time slot; and

based on receipt of antenna assignment information, scheduling autonomous communications from a second directional antenna of the given RFID tag reader during a second time slot in which multiple non-interfering antennas associated with the set of other tag readers are also permitted to communicate in second time slot.

25. A method as in claim 18, wherein the given RFID tag reader and set of other RFID tag readers each include multiple antennas on which to transmit in the monitored region, each of the multiple antennas being assigned for communication in one of multiple time slots.

26. A method comprising:

synchronizing a given RFID tag reader with at least one other RFID tag reader in a region, each RFID tag reader having at least one corresponding antenna to communicate in a region;

receiving antenna assignment information indicating in which of multiple possible time slots that corresponding antennas associated with the given RFID tag reader are permitted to transmit; and

utilizing the antenna assignment information to create an access schedule for the given RFID tag reader to communicate in the region.

27. A method as in claim 26 further comprising:

based on use of the access schedule for the given RFID tag reader, enabling the given RFID tag reader to communicate in the region at a same time as another RFID tag reader by enabling an antenna associated with the given RFID tag reader to communicate in the region at a same time slot as an antenna associated with the at least one other RFID tag reader.

28. A method as in claim 26, wherein synchronizing the set of RFID tag readers includes:

based on receipt of timing information, setting a system clock associated with the given RFID tag reader;

utilizing the system clock to identify a time slot in which the given RFID tag reader is permitted to communicate in the region via at least one antenna associated with the given RFID tag reader as specified by the antenna assignment information; and

initiating autonomous communications in the time slot without regard to when the at least one other RFID tag reader transmits RF energy in the region.

29. A method as in claim 26, wherein synchronizing the given RFID tag reader with at least one other RFID tag reader includes synchronizing the given RFID tag reader with a set of tag readers in a defined zone in which the set of tag readers can cause interference with each other.

30. A method as in claim 26, wherein receiving antenna assignment information includes:

for a first time-slotted communication cycle, receiving a first set of antenna assignment information indicating in which of multiple possible time slots of the first time-slotted communication cycle that corresponding antennas associated with the given RFID tag reader are permitted to transmit during execution of the first time-slotted communication cycle; and

for a second time-slotted communication cycle, receiving a second set of antenna assignment information indicating in which of multiple possible time slots of the second time-slotted communication cycle that corresponding antennas associated with the given RFID tag reader are permitted to transmit during execution of the second time-slotted execution cycle.

31. A method as in claim 26 further comprising:

initiating activation of the corresponding antennas associated with the given RFID tag reader in permitted time slots as identified by the antenna assignment information; and

reassigning at least one of the corresponding antennas to communicate in a different time slot in a following communication cycle of time-slotted communications.

32. A method as in claim 26 further comprising:

initiating transmissions of RF energy in a permitted direction from the given tag reader during a time slot as specified by the antenna assignment information without regard to when the at least one other RFID tag reader transmits RF energy in the region during the time slot.

33. A method comprising:

receiving transmitter information associated with multiple transducers that transmit RF energy in a monitored region;

based on the transmitter information, producing assignment information by assigning each of the multiple transducers a respective time slot for permitting transmission of RF energy in the monitored region; and

distributing the antenna assignment information to provide notification of which of multiple time slots when each of the multiple transducers are permitted to transmit the RF energy in the region.

34. A method as in claim 33, wherein producing the assignment information includes:

assigning a given transducer of the multiple transducers to a given time slot of multiple time slots based on feedback from at least one RFID tag readers that utilize the transducers to communicate with RFID tags in the monitored region.

35. A method as in claim 33, wherein producing the assignment information includes:

assigning a subset of the multiple transducers to communicate in a same time slot of a time-based channel access schedule in which the subset of multiple transducers communicate with RFID tags in the monitored region.

36. A method as in claim 33, wherein receiving coverage information includes receiving transducer information specifying corresponding directions in which the multiple transducers transmit RF energy in the monitored region.

37. A method as in claim 36, wherein producing assignment information includes:

selecting a first subset of the multiple transducers to produce a first group of non-interfering transducers;

allocating a first time slot in which the first group of non-interfering transducers are permitted to transmit in the monitored region;

selecting a second subset of the multiple transducers to produce a second group of non-interfering transducers; and

allocating a second time slot in which the second group of non-interfering transducers are permitted to transmit in the monitored region.

38. A method as in claim 33, wherein producing the assignment information includes:

providing diversity by dynamically modifying a grouping of the multiple transducers that are permitted to transmit RF energy in the monitored region during a given time slot.

39. A method as in claim 33, wherein receiving transmitter information includes receiving interference information indicating which of the multiple transducers interfere with each other when activated at the same time;

and

wherein producing the assignment information includes utilizing the interference information to assign non-interfering sets of transducers to a same corresponding time slot in which a respective set of non-interfering transducers is permitted to simultaneously initiate communications in the region.

40. A method as in claim 39 further comprising:

deriving the interference information via implementing a procedure in which at least one transducer of a corresponding RFID tag reader transmits RF energy while other RFID tag readers each monitor for a presence of RF energy produced by the at least one transducer.

41. A method as in claim 39 further comprising:

deriving the interference information via normal operation during which the multiple transducers are activated to transmit in respective assigned time slots to communicate with RFID tags in the monitored region.

42. A method comprising:

synchronizing a given RFID tag reader with other RFID tag readers;

receiving a set of rules about use of a wireless spectrum to communicate from multiple transmitters associated with the given RFID tag reader; and

in accordance with the set of rules, assigning the multiple transmitters of the given RFID tag reader to transmit in time slots of a shared time slotted access schedule, the shared time slotted access schedule used by the given RFID tag reader and the other RFID tag readers to communicate in a monitored region.

43. A method as in claim 42, wherein assigning the multiple transmitters of the given RFID tag reader to transmit in the time slots includes:

enabling more efficient RFID tag reads by assigning the multiple transmitters in different time slots based at least in part on statistical information maintained by the given RFID tag reader.

44. A method as in claim 42, wherein assigning the multiple transmitters of the given RFID tag reader to transmit in the time slots includes:

at least occasionally introducing a level of randomness when selecting which of the multiple transmitters to assign to the time slots.

45. A computer system comprising:

a processor;

a memory unit that stores instructions associated with code executed by the processor; and

an interconnect coupling the processor and the memory unit, enabling the computer system to execute the code and perform operations of;

receiving time reference information;

based on the timing reference information, synchronizing the wireless transceiver device with multiple other wireless transceiver devices that communicate in the monitored region; and

scheduling communications from the given wireless transceiver device to at least one of the multiple wireless identification tags in the monitored region.

46. A computer system as in claim 45, wherein receiving time reference information occurs in response to:

initiating communications over a respective network to retrieve the time reference information from a server for purposes of synchronizing wireless transmissions from the given wireless transceiver device with respect to wireless transmissions by the multiple other wireless transceiver devices that also communicate in the monitored region.

47. A computer system as in claim 45, wherein receiving time reference information includes receiving the time reference information from a respective GPS (Global Positioning System) device, the computer system further supporting operations of:

communicating with the GPS device to obtain respective location information for purposes of learning a respective whereabouts of the given wireless transceiver device.

48. A computer system as in claim 45, wherein scheduling communications includes selecting a particular one of multiple wireless channels or frequency bands as a carrier medium on which to communicate from the given wireless transceiver device to at least one of the wireless identification tags in the monitored region.

49. A computer system as in claim 45, wherein scheduling communications from the given wireless transceiver device includes:

scheduling the given wireless transceiver device to initiate wireless communications on a respective channel in the monitored region during a respective transmit duration in which at least one of the other wireless transceiver devices is also scheduled to transmit on the respective channel.

51. A computer system as in claim 45, wherein synchronizing the given wireless transceiver device causes the given wireless transceiver device to become part of a first zone of multiple zones of synchronized wireless transceiver devices, the first zone including the given wireless transceiver device and the multiple other wireless transceiver devices, a second zone of the multiple zones including a corresponding remote group of synchronized wireless transceiver devices i) that operate off of a unique master clock with respect to a corresponding master clock used to synchronize the wireless transceiver devices in the first zone and ii) that do not interfere with communications initiated by the wireless transceiver devices in the first zone.

52. A computer system as in claim 51 further supporting operations of:

scheduling the given wireless transceiver device in the first zone to initiate wireless transmissions while i) each of the other multiple wireless transceiver devices are disabled from transmitting, and ii) each wireless transceiver device in the second zone attempts to detect the wireless transmissions from the given wireless transceiver device transmitting in the first zone.

53. A computer system as in claim 45 further supporting operations of:

operating the given wireless transceiver device amongst at least one wireless transceiver device that communicates with the wireless identification tags in the monitored region but is not synchronized as part of a respective zone of synchronized wireless transceiver devices including the given wireless transceiver device and the multiple other wireless transceiver devices.

54. A computer system as in claim 45, wherein scheduling communications from the given wireless transceiver device includes:

utilizing the timing reference information to;

schedule a first time duration in which the given wireless transceiver device transmits an unmodulated wireless carrier signal to provide power to at least one of the multiple wireless identification tags in the monitored region;

schedule a second time duration in which the given wireless transceiver device transmits a modulated wireless carrier signal to communicate a message to the at least one wireless identification tag; and

schedule a third time duration in which the given wireless transceiver device simultaneously i) transmits the unmodulated wireless carrier signal to provide power to the at least one of the multiple wireless identification tag in the monitored region, and ii) receives a modulated signal from the wireless transceiver device to receive a response from the at least one wireless identification tag.

55. A computer system as in claim 45, wherein receiving time reference information includes receiving the time reference information in a form of a wireless synchronization signal.

56. A computer system as in claim 45, wherein more than one wireless transceiver device operates in a given region receiving different modes of time reference information synchronized to the same time reference information

57. A computer system as in claim 45, wherein multiple types of wireless transceivers are assigned different time slots such that only wireless transceivers of the same type transmit a during a given time slot.

59. A computer system as in claim 57, wherein the first type of wireless transceiver devices includes transmitters that make different spectral use of wireless channels than those in the second type of wireless transceiver devices.

60. A computer system as in claim 59, wherein the first type of wireless transceiver devices includes wireless transmitters that transmit at different respective power levels and use different communication protocols than wireless transmitters associated with the second type of wireless transceiver devices.

50. A computer system as in claim last 49, wherein scheduling the given wireless transceiver device to initiate wireless communications on the respective channel includes:

subdividing the transmit duration to include a first part and a second part;

scheduling the given wireless transceiver device to communicate on the respective channel during the first part of the time duration exclusive of the other wireless transceiver devices; and

disabling the given wireless transceiver device from communicating during the second part of the transmit duration which is apportioned for use by at least one of the other wireless transceiver devices to communicate in the monitored region.

58. A computer system as in claim last 57, wherein a first type of wireless devices is assigned to communicate in a first time slot of a time slotted access schedule shared by the wireless transceiver device and the other wireless transceiver devices that communicate in the monitored region;

and

wherein a second type of wireless devices is assigned to communicate in a second time slot of a time slotted access schedule.

61. A computer system comprising:

a processor;

a memory unit that stores instructions associated with code executed by the processor; and

an interconnect coupling the processor and the memory unit, enabling the computer system to execute the code and perform operations of;

receiving synchronization information;

utilizing the synchronization information to synchronize a given RFID tag reader with a set of other RFID tag readers; and

initiating communications from at least one antenna associated with the given RFID tag reader in assigned time slots.

62. A computer system as in claim 61 further supporting operations of:

receiving antenna assignment information indicating in which of multiple possible time slots that corresponding antennas associated with the given RFID tag reader are permitted to transmit RF energy for communicating with RFID tags in a monitored region; and

wherein initiating the communications from the at least one antenna associated with the given RFID tag reader includes initiating communications from at least one of the corresponding antennas in a permitted time slot as specified by the antenna assignment information to communicate with the RFID tags.

63. A computer system as in claim 62, wherein initiating the communications includes communicating in the permitted time slot based on a communication schedule associated with the given RFID tag reader.

64. A computer system as in claim 61 further supporting operations of:

receiving antenna assignment information from a centralized location that generates rules indicating in which of multiple time slots directional antennas associated with the given RFID tag reader and the set of other RFID tag readers are permitted to communicate with respective RFID tags.

65. A computer system as in claim 61, wherein initiating communications from the at least one antenna associated with the given RFID tag reader in assigned time slots includes:

communicating in a monitored region via a first directional antenna of the given RFID tag reader during a first time slot; and

communicating in the monitored region via a second directional antenna of the given RFID tag reader during a second time slot.

66. A computer system as in claim 61, wherein initiating communications from the at least one antenna associated with the given RFID tag reader in assigned time slots includes:

based on receipt of antenna assignment information, scheduling autonomous communications from a first directional antenna of the given RFID tag reader during a first time slot in which multiple non-interfering antennas associated with the set of other tag readers are also permitted to communicate in the first time slot; and

based on receipt of antenna assignment information, scheduling autonomous communications from a second directional antenna of the given RFID tag reader during a second time slot in which multiple non-interfering antennas associated with the set of other tag readers are also permitted to communicate in second time slot.

67. A computer system as in claim 61, wherein the given RFID tag reader and set of other RFID tag readers each include multiple antennas on which to transmit in the monitored region, each of the multiple antennas being assigned for communication in one of multiple time slots.

68. A computer system comprising:

a processor;

a memory unit that stores instructions associated with code executed by the processor; and

an interconnect coupling the processor and the memory unit, enabling the computer system to execute the code and perform operations of;

synchronizing a given RFID tag reader with at least one other RFID tag reader in a region, each RFID tag reader having at least one corresponding antenna to communicate in a region;

receiving antenna assignment information indicating in which of multiple possible time slots that corresponding antennas associated with the given RFID tag reader are permitted to transmit; and

utilizing the antenna assignment information to create an access schedule for the given RFID tag reader to communicate in the region.

69. A computer system as in claim 68 further supporting operations of:

based on use of the access schedule for the given RFID tag reader, enabling the given RFID tag reader to communicate in the region at a same time as another RFID tag reader by enabling an antenna associated with the given RFID tag reader to communicate in the region at a same time slot as an antenna associated with the at least one other RFID tag reader.

70. A computer system as in claim 68, wherein synchronizing the set of RFID tag readers includes:

based on receipt of timing information, setting a system clock associated with the given RFID tag reader;

utilizing the system clock to identify a time slot in which the given RFID tag reader is permitted to communicate in the region via at least one antenna associated with the given RFID tag reader as specified by the antenna assignment information; and

initiating autonomous communications in the time slot without regard to when the at least one other RFID tag reader transmits RF energy in the region.

71. A computer system as in claim 68, wherein synchronizing the given RFID tag reader with at least one other RFID tag reader includes synchronizing the given RFID tag reader with a set of tag readers in a defined zone in which the set of tag readers can cause interference with each other.

72. A computer system as in claim 68, wherein receiving antenna assignment information includes:

for a first time-slotted communication cycle, receiving a first set of antenna assignment information indicating in which of multiple possible time slots of the first time-slotted communication cycle that corresponding antennas associated with the given RFID tag reader are permitted to transmit during execution of the first time-slotted communication cycle; and

for a second time-slotted communication cycle, receiving a second set of antenna assignment information indicating in which of multiple possible time slots of the second time-slotted communication cycle that corresponding antennas associated with the given RFID tag reader are permitted to transmit during execution of the second time-slotted execution cycle.

73. A computer system as in claim 68 further supporting operations of:

initiating activation of the corresponding antennas associated with the given RFID tag reader in permitted time slots as identified by the antenna assignment information; and

reassigning at least one of the corresponding antennas to communicate in a different time slot in a following communication cycle of time-slotted communications.

74. A computer system as in claim 68 further supporting operations of:

initiating transmissions of RF energy in a permitted direction from the given tag reader during a time slot as specified by the antenna assignment information without regard to when the at least one other RFID tag reader transmits RF energy in the region during the time slot.

75. A computer system comprising:

a processor;

a memory unit that stores instructions associated with code executed by the processor; and

an interconnect coupling the processor and the memory unit, enabling the computer system to execute the code and perform operations of;

receiving transmitter information associated with multiple transducers that transmit RF energy in a monitored region;

based on the transmitter information, producing assignment information by assigning each of the multiple transducers a respective time slot for permitting transmission of RF energy in the monitored region; and

distributing the antenna assignment information to provide notification of which of multiple time slots when each of the multiple transducers are permitted to transmit the RF energy in the region.

76. A computer system as in claim 75, wherein producing the assignment information includes:

assigning a given transducer of the multiple transducers to a given time slot of multiple time slots based on feedback from at least one RFID tag readers that utilize the transducers to communicate with RFID tags in the monitored region.

77. A computer system as in claim 75, wherein producing the assignment information includes:

assigning a subset of the multiple transducers to communicate in a same time slot of a time-based channel access schedule in which the subset of multiple transducers communicate with RFID tags in the monitored region.

78. A computer system as in claim 75, wherein receiving coverage information includes receiving transducer information specifying corresponding directions in which the multiple transducers transmit RF energy in the monitored region.

79. A computer system as in claim 78, wherein producing assignment information includes:

selecting a first subset of the multiple transducers to produce a first group of non-interfering transducers;

allocating a first time slot in which the first group of non-interfering transducers are permitted to transmit in the monitored region;

selecting a second subset of the multiple transducers to produce a second group of non-interfering transducers; and

allocating a second time slot in which the second group of non-interfering transducers are permitted to transmit in the monitored region.

80. A computer system as in claim 75, wherein producing the assignment information includes:

providing diversity by dynamically modifying a grouping of the multiple transducers that are permitted to transmit RF energy in the monitored region during a given time slot.

81. A computer system as in claim 75, wherein receiving transmitter information includes receiving interference information indicating which of the multiple transducers interfere with each other when activated at the same time;

and

wherein producing the assignment information includes utilizing the interference information to assign non-interfering sets of transducers to a same corresponding time slot in which a respective set of non-interfering transducers is permitted to simultaneously initiate communications in the region.

82. A computer system as in claim 81 further supporting operations of:

deriving the interference information via implementing a procedure in which at least one transducer of a corresponding RFID tag reader transmits RF energy while other RFID tag readers each monitor for a presence of RF energy produced by the at least one transducer.

83. A computer system as in claim 81 further supporting operations of:

deriving the interference information via normal operation during which the multiple transducers are activated to transmit in respective assigned time slots to communicate with RFID tags in the monitored region.

84. A computer system comprising:

a processor;

a memory unit that stores instructions associated with code executed by the processor; and

an interconnect coupling the processor and the memory unit, enabling the computer system to execute the code and perform operations of;

synchronizing a given RFID tag reader with other RFID tag readers;

receiving a set of rules about use of a wireless spectrum to communicate from multiple transmitters associated with the given RFID tag reader; and

in accordance with the set of rules, assigning the multiple transmitters of the given RFID tag reader to transmit in time slots of a shared time slotted access schedule, the shared time slotted access schedule used by the given RFID tag reader and the other RFID tag readers to communicate in a monitored region.

85. A computer system as in claim 84, wherein assigning the multiple transmitters of the given RFID tag reader to transmit in the time slots includes:

enabling more efficient RFID tag reads by assigning the multiple transmitters in different time slots based at least in part on statistical information maintained by the given RFID tag reader.

86. A computer system as in claim 84, wherein assigning the multiple transmitters of the given RFID tag reader to transmit in the time slots includes:

at least occasionally introducing a level of randomness when selecting which of the multiple transmitters to assign to the time slots.

87. Software encoded in one or more computer-readable media and, when executed, operable to:

receive time reference information;

based on the timing reference information, synchronize the wireless transceiver device with multiple other wireless transceiver devices that communicate in the monitored region; and

schedule communications from the given wireless transceiver device to at least one of the multiple wireless identification tags in the monitored region.

88. Software encoded in one or more computer-readable media and, when executed, operable to:

receive synchronization information;

utilize the synchronization information to synchronize a given RFID tag reader with a set of other RFID tag readers; and

initiate communications from at least one antenna associated with the given RFID tag reader in assigned time slots.

89. Software encoded in one or more computer-readable media and, when executed, operable to:

synchronize a given RFID tag reader with at least one other RFID tag reader in a region, each RFID tag reader having at least one corresponding antenna to communicate in a region;

receive antenna assignment information indicating in which of multiple possible time slots that corresponding antennas associated with the given RFID tag reader are permitted to transmit; and

utilize the antenna assignment information to create an access schedule for the given RFID tag reader to communicate in the region.

90. Software encoded in one or more computer-readable media and, when executed, operable to:

receive transmitter information associated with multiple transducers that transmit RF energy in a monitored region;

based on the transmitter information, produce assignment information by assigning each of the multiple transducers a respective time slot for permitting transmission of RF energy in the monitored region; and

distribute the antenna assignment information to provide notification of which of multiple time slots when each of the multiple transducers are permitted transmit the RF energy in the region.