Patexia seeks prior art for a US patent which allegedly describes a method of changing the number of times a hybrid automatic repeat request (HARQ) process can occur when transitioning between multiple-input multiple-output (MIMO) and non-MIMO operation to avoid the accidental and unpredictable combination of data redundancy packets that were never intended to be combined.

In order to improve the transmission of data to and from a mobile device in a cellular network, two different technologies were developed:

• Hybrid Automatic Repeat Request (HARQ) was developed as a method to correct data when it is received with errors. By automatically requesting a retransmission, the receiver can get more and more data packets to correct any received errors, and eventually rebuild the data without any errors.
• Multiple-Input and Multiple-Output (MIMO) was developed as a method of increasing data bandwidth by allowing a receiver to use multiple antennas to collect multiple radio signals. With each signal carry unique data, a receiver can essentially multiply the amount of data it can receive at a particular time.

While these technologies greatly helped increase the data transmission reliability to and from a mobile device, these two technologies are not seamlessly compatible. When in non-MIMO operation, a mobile device is limited to 8 HARQ processes at most, essentially limiting the number of times a mobile device can request a retransmission. When in MIMO mode, this number of HARQ processes increases, but must be either 12, 14, or 16.

Transitioning between non-MIMO to MIMO operation requires adjusting this number of HARQ processes. Incorrectly handling this transition could cause the incorrect number of data packets to be recombined, resulting in unpredictable combinations of non-compatible data packets.

To handle this transition, the patent describes the following steps:

• when transitioning from non-MIMO to MIMO:
• adding a variable to the radio resource control message to describe HARQ information sent as a physical channel reconfiguration message
• at the mobile device, checking if a set of conditions is met
• at the mobile device, checking if the number of HARQ processes is an even number
• then transition to MIMO operation
• when transitioning from MIMO to non-MIMO
• adjusting the number of HARQ processes back to the non-MIMO setting
• then transitioning to non-MIMO operation

This Contest is related to the following Mobile Phone Connection Contests. Similar references are allowed; however, the five Contests focus on different features and have different questions. All five Contests have the same list of Known References.

1. Data Division of a Service Data Unit
2. HARQ Control of MIMO Handoff
3. Efficient Random Access Preamble Procedure
4. RLC Variable Reset
5. HARQ with TTI Bundling

Overview of the method to improve HARQ operation when transitioning between MIMO to non-MIMO operation

Questions

1. Was the reference filed or published before June 13th, 2007?
2. Does the reference describe a method to improve the Hybrid Automatic Repeat Request (HARQ) operation of a wireless network by having a mobile device switch to a multiple-input, multiple-output (MIMO) mode only when a request is made via the radio resource control method, a set of conditions have been met, and the number of HARQ processes is set to the correct value to support MIMO operation?
3. Does the reference describe this mobile device that switches to a MIMO mode having a control circuit, a central processing unit in the control circuit to execute code for improving the HARQ operation, and a memory coupled to the CPU to store this code?
4. Does the method to improve the HARQ operation add a variable describing HARQ information into a radio resource control message, and send this to the mobile device?
5. Is this radio resource control message formatted as a physical channel reconfiguration message, and is used by the network to control the physical channel used by the mobile device either by initially assigning a channel, transitioning to a different channel, or releasing the channel back to the system?
6. Upon receiving the radio resource control message, does the method control the message to prevent it from unilaterally changing the MIMO mode status of the mobile device?
7. Does the method then allow the mobile device to enter MIMO mode operation only when a set of conditions is met and the variable added earlier to describe the number of HARQ processes is set to an even number?
8. When returning to non-MIMO mode from MIMO operation, does the method further adjust the number of HARQ processes to the appropriate setting for non-MIMO operation?