Rach ramp-up acknowledgement

• US 7,359,427 B2
• Filed: 04/14/2003
• Issued: 04/15/2008
• Est. Priority Date: 03/22/1999
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Golden Bridge Technology Incorporated
• Inventors: Kanterakis, Emmanuel, Parsa, Kourosh
• Primary Examiner(s): Bocure, Tesfaldet
• Application Number:
  US10/412,576
• Publication Number:
  US 20030223476A1
• Time in Patent Office: 1,828 Days
• Field of Search: 375362-368, 375144-148, 375/130, 375/140, 375/141, 375/377, 375/259, 375/143, 375/149, 375/152, 370/328, 370/335, 370/342, 370/345, 370/347, 370/442, 370/445, 370/218, 370525-529, 370/503, 370/278, 370/441, 455/515, 455/450, 455/516, 455/509, 455/517, 455/513, 455/500
• US Class Current: 375/141
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 2201/70701 featuring pilot assisted reception
• CPC Class Codes: H04B 2201/70702 Intercell-related aspects
• CPC Class Codes: H04B 7/2668 Arrangements for Wireless Code-Division Multiple Access [CDMA] System Synchronisation, for code acquisition H04B1/7075, for code tracking H04B1/7085
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/362 Aspects of the step size
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/48 during retransmission after error or non-acknowledgment
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 74/00 Wireless channel access

Abstract

An improvement to a code-division-multiple-access (CDMA) system employing spread-spectrum modulation, with the CDMA system having a base station (BS) and a plurality of remote stations. The base station has a BS-spread-spectrum transmitter and a BS-spread-spectrum receiver. A remote station has an RS-spread-spectrum transmitter and an RS-spread-spectrum receiver. The BS transmitter transmits a broadcast common-synchronization channel, which includes a frame-timing signal. The broadcast common-synchronization channel has a common chip-sequence signal, which is common to the plurality of remote stations. In response to the RS-spread-spectrum receiver receiving the broadcast common-synchronization channel, and determining frame timing from the frame-timing signal, an RS-spread-spectrum transmitter transmits an access-burst signal. The access-burst signal includes a collision-detection portion. In response to the BS-spread-spectrum receiver receiving the access-burst signal, the BS-spread-spectrum transmitter transmits an collision-detection signal with the collision detection portion. In response to the BS-spread-spectrum receiver not receiving the access-burst signal due to a collision with a collision access-burst signal, the BS-spread-spectrum transmitter transmits an collision-detection signal without the correct collision detection portion.

Claims

1. A method of sending packet data from a remote station, the method comprising:

receiving a broadcast common channel from a base station;

determining at least one parameter required for transmission to the base station from the received broadcast common channel;

transmitting an access-burst signal, the access-burst signal comprising a plurality of segments, each segment comprising a selected access preamble and a pilot signal, the preambles having sequentially increasing discrete power levels;

if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission; and

upon detecting an acknowledgment comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission, and spread-spectrum transmitting the packet data from the remote station.

2. The method as in claim 1, wherein power level of the pilot signal is set to a zero power level.

3. The method as in claim 1, wherein the pilot signals of the plurality of segments of the access-burst signal have sequentially increasing descrete power levels.

4. The method as in claim 1, wherein the step of determining at least one parameter comprises determining timing of the transmission of at least one of the access preambles.

5. A method as in claim 1, wherein the determining step comprises choosing the selected preamble from among a set of predefined preambles associated with a base station.

6. The method of claim 1, wherein the acknowledgement is a level 1 acknowledgement.

7. The method of claim 1, wherein the power level of the pilot signal is less than the power level of the preamble.

8. A method of sending packet data from a remote station, the method comprising:

receiving a broadcast common channel from a base station;

determining at least one parameter required for transmission to the base station from the received broadcast common channel, comprising determining timing of the transmission of at least one of the access preambles by randomly choosing one of a plurality of time slots defined in relation to the received broadcast common channel to start the transmitting of the access burst signal;

transmitting an access-burst signal, the access-burst signal comprising a plurality of segments having a plurality of constant power levels, each segment comprising a selected access preamble and a pilot signal;

if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission; and

upon detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission, and spread-spectrum transmitting the packet data from the remote station.

9. A remote station for wireless communication with a base station of a network, the remote station comprising:

a spread-spectrum transmitter;

a spread-spectrum receiver; and

a controller coupled to the receiver for responding to signals received via the receiver and coupled for controlling the transmitter, such that in operation the remote station is for performing the following steps;

(a) transmitting an access-burst signal, the access-burst signal comprising a plurality of segments having sequentially increasing discrete power levels, each segment comprising a selected access preamble;

(b) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission; and

(c) upon detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission, and spread-spectrum transmitting the packet data from the remote station,

wherein the spread-spectrum transmitter comprises;

(1) a spreading sequence generator;

(2) a product device coupled to an output of the spreading sequence generator and coupled to receive an access preamble and the packet data; and

(3) a digital analog converter responsive to an output of the product device.

10. A remote station for wireless communication with a base station of a network, the remote station comprising:

a spread-spectrum transmitter;

a spread-spectrum receiver; and

a controller coupled to the receiver for responding to signals received via the receiver and coupled for controlling the transmitter, such that in operation the remote station is for performing the following steps;

(a) transmitting an access-burst signal, the access-burst signal comprising a plurality of segments having sequentially increasing discrete power levels, each segment comprising a selected access preamble;

(b) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission; and

(c) upon detecting an acknowledgement comprising a signal corresponding to a transmitted access preamble, ceasing preamble transmission, an spread-spectrum transmitting the packet data from the remote station,

wherein the spread-spectrum receiver comprises;

(1) an analog to digital converter responsive to a signal received by the remote station; and

(2) a programmable matched filter responsive to an output of the analog to digital converter.

11. A base-band processor for use in a wireless remote station for communication of data, the remote station having a spread-spectrum modulator and a spread-spectrum demodulator, the base-band processor comprising:

an acknowledgment detector, coupled to the demodulator, for detecting an acknowledgment in a received spread-spectrum signal;

a preamble generator for generating access preamble signals;

a multiplexer for multiplexing the data and the access preamble signals and supplying the multiplexed data and access preamble signals to the modulator for transmission; and

a controller coupled to the acknowledgment detector and coupled for controlling the modulator, the preamble generator and the multiplexer, such that in operation the remote station performs the following steps;

(a) spreading an access preamble selected from a set of predefined preamble, associated with the base station;

(b) transmitting from the remote station an access-burst signal, the access-burst signal comprising a plurality of segments having sequentially increasing discrete power levels, each segment comprising the spread selected access preamble;

(c) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to the transmitted access preamble, ceasing preamble transmission; and

(d) upon detecting an acknowledgement comprising a signal corresponding to the transmitted access preamble, ceasing preamble transmission, and spread-spectrum transmitting the packet data from the remote station.

12. The base-band processor as in claim 11, further comprising:

an encoder, for encoding data; and

an interleaver, coupled to the encoder, for interleaving encoded data and supplying the interleaved data to the multiplexer for multiplexing with the access preamble signals.

13. A base-band processor for use in a wireless remote station for communication of data, the remote station having a spread-spectrum modulator and a spread-spectrum demodulator, the base-band processor comprising:

an acknowledgement detector, coupled to the demodulator, for detecting an acknowledgment in a received spread-spectrum signal;

a preamble generator for generating access preamble signals;

a multiplexer for multiplexing the data and the access preamble signals and supplying the multiplexed data and access preamble signals to the modulator for transmission;

an encoder, for encoding data;

an interleaver, coupled to the encoder, for interleaving encoded data and supplying the interleaved data to the multiplexer for multiplexing with the access preamble signals;

a packet formatter, coupled to the multiplexer, for formatting the multiplexed data and access preamble signals into one or more packets and supplying the one or more packets to the modulator; and

a controller coupled to the acknowledgement detector and coupled for controlling the modulator, the preamble generator and the multiplexer, such that in operation the remote station performs the following steps;

(a) spreading an access preamble selected from a set of predefined preambles associated with the base station;

(b) transmitting from the remote station an access-burst signal, the access-burst signal comprising a plurality of segments having a plurality of constant power levels, each segment comprising the spread selected access preamble;

(c) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to the transmitted access preamble, ceasing preamble transmission; and

(d) upon detecting an acknowledgement comprising a signal corresponding to the transmitted access preamble, ceasing preamble transmission, and spread-spectrum transmitting the packet data from the remote station.

14. A method of sending data from a remote station to at least one of a plurality of base stations in a spread-spectrum wireless communication network, comprising:

receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations;

receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations;

determining to transmit to the first base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

transmitting a first access-burst signal to the first base station, the first access-burst signal comprising a plurality of segments having sequentially increasing discrete power levels, each segment comprising an access preamble;

if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement signal, ceasing access-burst transmission; and

upon receiving and detecting a first acknowledgment signal corresponding to a transmitted access preamble, from the first base station, ceasing access-burst transmission and transmitting a first spread-spectrum signal having data to the first base station.

15. The method as in claim 14, wherein the plurality of segments of the first access-burst signal have sequentially increasing discrete power levels.

16. The system as in claim 15, wherein:

the first access burst signal comprises a preamble code selected from among a plurality of preamble codes allocated to the first base station;

the step of transmitting the first access-burst signal comprises spreading the selected preamble code; and

the first acknowledgment signal corresponds to the selected preamble code.

17. The method as in claim 14, further comprising receiving data or power control information from the first base station.

18. The method as in claim 14, further comprising:

determining to transmit to the second base station, based on any of power levels and probabilities of error, front the first and second broadcast common-synchronization channels;

transmitting a second access-burst signal to the second base station, the second access-burst signal comprising a plurality of segments having sequentially increasing discrete power levels, each segment comprising an access preamble;

if the number of transmissions of an access preamble to the second base station has reached a maximum allowed number of preambles Mp without detecting an acknowledgement signal, ceasing access-burst transmission; and

upon receiving and detecting a second acknowledgement signal from the second base station, the second acknowledgment signal corresponding to the an access preamble transmitted to the second base station, ceasing access-burst transmission and transmitting a second spread-spectrum signal having data to the second base station.

19. The method as in claim 18, wherein the plurality of segments at the second access burst signal have sequentially increasing discrete power levels.

20. The method as in claim 18, wherein:

the second access burst signal comprises a preamble code selected from among a plurality of preamble codes allocated to the second base station;

the step of transmitting the second access-burst signal comprises spreading the preamble code selected from among the preamble codes allocated to the second base station; and

the second acknowledgment signal corresponds to the preamble code selected from among the preamble codes allocated to the second base station.

21. The method as in claim 18, further comprising receiving data or power control information from the second base station.

22. The method of claim 18, wherein the acknowledgement is a level 1 acknowledgement.

23. The method fo claim 18, wherein the power level of the pilot signal is less than the power level of the preamble.

24. The method of claim 14, wherein the acknowledgement is a level 1 acknowledgement.

25. The method of claim 14, wherein the power level of the pilot signal is less than the power level of the preamble.

26. A remote station for wireless communication with a base station of a network, the remote station comprising:

a spread-spectrum transmitter;

a spread-spectrum receiver; and

a controller coupled to the receiver for responding to signals received via the receiver and coupled for controlling the transmitter, such that in operation the remote station is for performing the following steps;

(a) receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations;

(b) receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations;

(c) determining to transmit to the first base station, based on any of power levels and probabilities of error, front the first and second broadcast common-synchronization channels;

(d) transmitting an access-burst signal to the first base station comprising a plurality of segments with sequentially increasing discrete power levels, each segment comprising an access preamble;

(e) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement signal, ceasing access-burst signal transmission; and

(f) upon receiving and detecting an acknowledgment signal corresponding to a transmitted access preamble, from the first base station, ceasing transmission of the access-burst signal and transmitting a first spread-spectrum signal having data to the first base station.

27. The remote station as in claim 26, wherein the spread-spectrum transmitter comprises:

a spreading sequence generator;

a product device coupled to an output of the spreading sequence generator and coupled to receive an access preamble and the packet data; and

a digital to analog convener responsive to an output of the product device.

28. The remote station as in claim 26, wherein the spread-spectrum receiver comprises:

an analog to digital converter responsive to a signal received by the remote station; and

a programmable matched filter responsive to an output of the analog in digital converter.

29. A base-band processor, for use in a wireless remote station for communication of data, the remote station having a spread-spectrum modulator and a spread-spectrum demodulator, the base-band processor comprising:

an acknowledgment detector, coupled to the demodulator, for detecting an acknowledgement in a received spread-spectrum signal;

a preamble generator for generating access preamble signals;

a multiplexer for multiplexing the data and the access preamble signals and supplying the multiplexed data and access preamble signals to the modulator for transmission; and

a controller coupled to the acknowledgment detector and coupled for controlling the modulator, the preamble generator and the multiplexer, such that in operation the remote station performs the following steps;

(a) receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations;

(b) receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations;

(c) determining to transmit to the first base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

(d) transmitting an access-burst signal to the first base station comprising a plurality of segments with sequentially increasing discrete power levels, each segment comprising an access preamble;

(e) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement signal, ceasing access-burst signal transmission; and

(f) upon receiving and detecting an acknowledgement signal corresponding to a transmitted access preamble, from the first base station, ceasing transmission of the access-burst signal and transmitting a spread-spectrum signal having data to the first base station.

30. The base-band processor as in claim 29, further comprising:

an encoder, for encoding data; and

an interleaver, coupled to the encoder, for interleaving encoded data and supplying the interleaved data to the multiplexer for multiplexing with the access preamble signals.

31. A base-band processor, for use in a wireless remote station for communication of data, the remote station having a spread-spectrum modulator and a spread-spectrum demodulator, the base-band processor comprising:

an acknowledgement detector, coupled to the demodulator, for detecting an acknowledgement in a received spread-spectrum signal;

a preamble generator for generating access preamble signals;

a multiplexer for multiplexing the data and the access preamble signals and supplying the multiplexed data and access preamble signals to the modulator for transmission;

an encoder, for encoding data;

an interleaver, coupled to the encoder, for interleaving encoded data and supplying the interleaved data to the multiplexer for multiplexing with the access preamble signals;

a packet formatter, coupled to the multiplexer, for formatting the multiplexed data and access preamble signals into one or more packets and supplying the one or more packets to the modulator; and

a controller coupled to the acknowledgement detector and coupled for controlling the modulator, the preamble generator and the multiplexer, such that in operation the remote station performs the following steps;

(a) receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations;

(b) receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations;

(c) determining to transmit to the first base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

(d) transmitting an access-burst signal to the first base station comprising a plurality of segments with a plurality of constant power levels, each segment comprising an access preamble;

(e) if the number of transmitted access preambles has reached a maximum allowed number of preambles Mp without detecting an acknowledgement signal, ceasing access-burst signal transmission; and

(f) upon receiving and detecting an acknowledgement signal corresponding to a transmitted access preamble, from the first base station, ceasing transmission of the access-burst signal and transmitting a spread-spectrum signal having data to the first base station, a packet formatter, coupled to the multiplexer, for formatting the multiplexed data and access preamble signals into one or more packets and supplying the one or more packets to the modulator.

32. A method of sending data from a remote station to at least one of a plurality of base stations in a spread-spectrum wireless communication network, comprising:

receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations, the first broadcast common-synchronization channel having a first frame-timing signal;

receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations, the second broadcast common-synchronization channel having a second frame-timing signal;

determining to transmit to the first base station, based on at least one parameter of the received first and second broadcast common-synchronization channels;

spreading an access preamble selected from a set of predefined preambles associated with the first base station;

transmitting an access-burst signal, the access-burst signal having a plurality of segments, each segment comprising a selected access preamble and a pilot signal, the preamble having a sequentially increasing discrete power levels;

if the number of transmissions of the access preamble has reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising a signal corresponding to the transmitted access preamble, ceasing preamble transmission; and

upon detecting an acknowledgement corresponding to the transmitted access preamble, ceasing preamble transmission and transmitting a first spread-spectrum signal having data, to the first base station.

33. The method as in claim 32, further comprising:

determining to transmit to the second base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

spreading another access preamble selected from a set of predefined preambles associated with the second base station;

transmitting an access-burst signal, the access-burst signal having a plurality of segments having sequentially increasing discrete power levels, each segment comprising the spread selected access preamble of the second base station and a pilot signal;

if the number of transmissions of the access preamble of the second base station has reached a maximum allowed number of reached a maximum allowed number of preambles Mp without detecting an acknowledgement comprising signal corresponding to the transmitted access preamble of the second base station, ceasing preamble transmission; and

upon detecting an acknowledgement corresponding to the transmitted access preamble of the second base station, ceasing preamble transmission and transmitting a second spread-spectrum signal having data, to the second base station.

34. The method of claim 33, wherein the acknowledgement is a level 1 acknowledgement.

35. the method of claim 33, wherein the power level of the pilot signal is less than the power level of the preamble.

36. A method of sending data from a remote station to at least one of a plurality of base stations in a spread-spectrum wireless communication network, comprising:

receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations;

receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations;

determining to transmit to the first base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

transmitting a first access-burst signal to the first base station, the first access-burst signal comprising a plurality of segments having a plurality of constant power levels, each segment comprising an access preamble and a pilot signal, wherein the power level of each segment is greater than zero;

receiving and detecting a first acknowledgement signal from the first base station corresponding to a transmitted access preamble;

ceasing access-burst transmission; and

transmitting a first spread-spectrum signal having data to the first base station.

37. A method of sending data from a remote station to at least one of a plurality of base stations in a spread-spectrum wireless communication network, comprising:

receiving from a first base station, a first broadcast common-synchronization channel having a first common chip-sequence signal common to a plurality of remote stations, the first broadcast common-synchronization channel having a first frame-timing signal;

receiving from a second base station, a second broadcast common-synchronization channel having a second common chip-sequence signal common to a plurality of remote stations, the second broadcast common-synchronization channel having a second frame-timing signal;

determining to transmit to the first base station, based on at least one parameter of the received first and second broadcast common-synchronization channels;

spreading an access preamble selected from a set of predefined preambles associated with the first base station;

transmitting an access-burst signal, the access-burst signal having a plurality of segments having a plurality of constant power levels, each segment comprising the spread selected access preamble and a pilot signal, wherein the power level of each segment is greater than zero;

detecting an acknowledgement from the first base station, the acknowledgement corresponding to the transmitted access preamble;

ceasing preamble transmission; and

transmitting a first spread-spectrum signal having data, to the first base station.

38. The method as in claim 37, further comprising:

determining to transmit to the second base station, based on any of power levels and probabilities of error, from the first and second broadcast common-synchronization channels;

spreading another access preamble selected from a set of predefined preambles associated with the second base station;

transmitting an access-burst signal, the access-burst signal having a plurality of segments having a plurality of constant power levels, each segment comprising the spread selected access preamble of the second base station and a pilot signal, wherein the power level of each segment is greater than zero;

detecting an acknowledgement from the second base station, the acknowledgement corresponding to the transmitted access preamble;

ceasing preamble transmission; and

transmitting a second spread-spectrum signal having data, to the second base station.