Time and bandwidth scalable slot for mobile data system

• US 6,721,267 B2
• Filed: 01/16/2001
• Issued: 04/13/2004
• Est. Priority Date: 08/01/2000
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Logalbo, Robert D., Doberstein, Kevin G., Hiben, Bradley M., Newberg, Donald G.
• Primary Examiner(s): Rao, Seema S.
• Assistant Examiner(s): Duong, Frank
• Application Number:
  US09/760,984
• Publication Number:
  US 20020031189A1
• Time in Patent Office: 1,183 Days
• Field of Search: 370/203, 370/204, 370/206, 370/210, 370/464, 370/465, 370/468, 370/476, 370/491, 370/510, 370/347, 375/340, 375/260, 375/261, 375/364, 375/298
• US Class Current: 370/206
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A scalable slot format defining positions of synchronization symbols, pilot symbols and data symbols for various numbers of sub-channels and various lengths of time in a multi-carrier communication system. An initial pattern (500) and one or more follow-on patterns (600, 700) are defined identifying positions of data symbols, synchronization symbols and pilot symbols for a first number of sub-channels corresponding to a first bandwidth. An extended pattern is constructed from the one or more follow-on patterns. The extension pattern is appended to the initial pattern to form a base pattern (810, 910, 1010). The base pattern (810, 910, 1010) is replicated zero or more times to form an expanded pattern (812, 910, 1015) identifying positions of data symbols, synchronization symbols and pilot symbols for an expanded number of sub-channels corresponding to a second bandwidth. The slot format may be implemented by a transmitter (100) having subdivided an original information signal into M bit streams and having encoded each of the M bit streams to 16QAM symbols to form M symbol streams, by inserting synchronization and pilot symbols into each of the M symbol streams at positions determined by the expanded pattern.

Claims

1. A method comprising the step of transmitting a time slot comprising two or more replications of a base pattern defining positions of data symbols, synchronization symbols and pilot symbols for a first number of sub-channels corresponding to a first bandwidth,

wherein the base pattern comprises an initial pattern identifying positions of data symbols, synchronization symbols and pilot symbols for the first number of sub-channels corresponding to the first bandwidth, and an extension pattern appended to the initial pattern, the extension pattern comprising one or more follow on patterns consecutively joined so that they identify positions of data symbols, synchronization symbols and pilot symbols for the first number of sub-channels corresponding to the first bandwidth, and

wherein the two or more replications in combination define positions of data symbols, synchronization symbols and pilot symbols for a second number of sub-channels corresponding to a second bandwidth.

2. The method of claim 1 wherein the extension pattern comprises only one follow-on pattern.

3. The method of claim 1 wherein the extension pattern comprises a plurality of consecutively joined follow-on patterns.

4. The method of claim 3 wherein the extension pattern comprises two consecutively joined follow-on patterns.

5. The method of claim 4 wherein the follow-on patterns comprise first and second types of follow-on patterns and wherein the extension pattern comprises one of the first type of follow-on patterns consecutively joined to one of the second type of follow-on patterns.

6. The method of claim 5 wherein the positions of synchronization symbols, pilot symbols and data symbols defined in the second type of follow-on pattern correspond substantially to the positions of synchronization symbols, pilot symbols and data symbols defined in the first type of follow-on pattern.

7. The method of claim 6 wherein the second type of follow-on pattern differs from the first type of follow-on pattern only in the last position of synchronization symbols, pilot symbols and data symbols in each of the first number of sub-channels.

8. The method of claim 1 wherein the base pattern spans a length of approximately 15 milliseconds, the initial pattern spans a length of 5 milliseconds and each of the one or more follow-on patterns spans a length of approximately 5 milliseconds.

9. The method of claim 2 wherein the base pattern spans a length of approximately 10 milliseconds, the initial pattern spans a length of 5 milliseconds and the extension pattern spans a length of approximately 5 milliseconds.

10. The method of claim 1 wherein the time slot comprises two replications of the base pattern.

11. The method of claim 1 wherein the time slot comprises three replications of the base pattern.

12. A method comprising the step of transmitting a time slot comprising at least one replication of a base pattern defining positions of data symbols, synchronization symbols and pilot symbols for a first number of sub-channels corresponding to a first bandwidth,

wherein the base pattern comprises an initial pattern identifying positions of data symbols, synchronization symbols and pilot symbols for the first number of sub-channels corresponding to the first bandwidth, and an extension pattern appended to the initial pattern, the extension pattern comprising a plurality of follow on patterns consecutively joined so that they identify positions of data symbols, synchronization symbols and pilot symbols for the first number of sub-channels corresponding to the first bandwidth, and

wherein the at least one replication of the base pattern defines positions of data symbols, synchronization symbols and pilot symbols for a second number of sub-channels corresponding to a second bandwidth.

13. The method of claim 12 wherein the extension pattern comprises four consecutively joined identical follow-on patterns.

14. The method of claim 13 wherein the extension pattern further comprises an additional follow-on pattern consecutively joined to the four identical follow-on patterns.

15. The method of claim 14 wherein the positions of data symbols, synchronization symbols and pilot symbols of the additional follow-on pattern correspond substantially to the positions of data symbols, synchronization symbols and pilot symbols in each of the four identical follow-on patterns.

16. The method of claim 15 wherein the additional follow-on pattern differs from the four identical follow-on patterns only in the last position of data symbols, synchronization symbols and pilot symbols in each of the first number of sub-channels.

17. The method of claim 14 wherein the base pattern spans a time of 30 milliseconds, the initial pattern spans a time of 5 milliseconds, each of the four identical follow-on patterns spans a time of 5 milliseconds and the additional follow-on pattern spans a time of approximately 5 milliseconds.

18. The method of claim 12 wherein the base pattern spans a time of 30 milliseconds.

19. The method of claim 12 wherein the time slot comprises one replication of the base pattern so that the base pattern and time slot are identical.

20. A method comprising a communication device performing the steps of:

receiving an information signal and subdividing the information signal into M bit streams;

encoding each of the M bit streams to data symbols to form M symbol streams;

inserting synchronization and pilot symbols into each of the M symbol streams at positions determined by an expanded pattern, yielding M composite symbol streams filling a time-division multiplex slot, the expanded pattern comprising at least one replication of a base pattern identifying positions of the synchronization symbols and pilot symbols for a subset of the M composite symbol streams, the base pattern comprising an extension pattern appended to an initial pattern, the initial pattern defining positions of the synchronization symbols and pilot symbols for the subset of the M composite streams for a portion of the time division multiplex slot and the extension pattern comprising a plurality of identical follow-on patterns consecutively joined, the follow-on patterns defining positions of the synchronization symbols and pilot symbols for the subset of the M composite streams for a portion of the time division multiplex slot;

modulating separate carrier signals with each of the M composite symbol streams, yielding M sub-channels centered about a center frequency;

combining the M sub-channels into a composite signal; and

transmitting the composite signal over an RF channel.