Increasing performance in communications by embedding one signal in another signal

• US 6,285,663 B1
• Filed: 06/05/1998
• Issued: 09/04/2001
• Est. Priority Date: 06/05/1998
• Status: Expired due to Term

• Current Assignee: Lenovo Innovation Company Limited Hong Kong (Lenovo Group Ltd.)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Esmailzadeh, Riaz
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US09/092,381
• Time in Patent Office: 1,187 Days
• Field of Search: 370/522, 370/527, 370/311, 499/522
• US Class Current: 370/311
• CPC Class Codes: H04J 3/125 One of the channel pulses or the synchronisation pulse is also used for transmitting monitoring or supervisory signals
• CPC Class Codes: H04J 3/14 Monitoring arrangements for SDH/SONET rings H04J3/085
• CPC Class Codes: H04W 52/60 using different transmission rates for TPC commands

Abstract

In transmitting communication signals to a receiver via a transmission channel, the transmitter generates a composite signal including information from which the receiver can determine a channel evaluation signal and other control information. The composite signal is transmitted over the transmission channel. This results in improved channel capacity, reduced power transmission requirements, and reduced interference in the transmission channel.

Claims

1. A transmitter for transmitting communication signals to a receiver via a transmission channel, comprising:

an apparatus for providing a channel evaluation signal and other control information which are to be used by the receiver;

a composite signal generator having an input coupled to said apparatus to receive said channel evaluation signal and said other control information, said signal generator being operable to embed said other control information exclusively in said channel evaluation signal, said composite signal generator having an output responsive to said channel evaluation signal and said other control information to produce a composite signal including composite information from which the receiver can determine said channel evaluation signal and said other control information; and

a transmit interface coupled to said output of said composite signal generator for interfacing between said composite signal generator and the transmission channel.

2. The transmitter of claim 1, wherein said composite signal generator includes a modulator coupled to said input to receive said channel evaluation signal, and an encoder coupled to said input to receive said other control information, said encoder having an output for providing encoded control information representative of said other control information, said modulator coupled to said encoder output for modulating said channel evaluation signal with said encoded control information to produce said composite signal, said modulator coupled to said composite signal generator output to provide thereto said composite signal.

3. The transmitter of claim 1, wherein said composite signal requires less transmission time over the transmission channel than would be needed to transmit said channel evaluation signal and said other control information as separate signals.

4. The transmitter of claim 1, wherein said composite signal requires less transmission power than would be needed to transmit said channel evaluation signal and said power control information as separate signals.

5. The transmitter of claim 1, wherein said composite signal creates less interference in the transmission channel than would be created by transmitting said channel evaluation signal and said power control information as separate signals.

6. The transmitter of claim 1, wherein the transmission channel includes a CDMA transmission channel of a cellular telecommunications system.

7. The transmitter of claim 1, wherein the transmission channel is a radio channel and said channel evaluation signal includes pilot symbols used to evaluate the radio channel.

8. The transmitter of claim 7, wherein said other control information includes power control information used in controlling transmission power in the radio channel.

9. A receiver for receiving communication signals from a transmitter via a transmission channel, comprising:

an extractor having an input to receive a composite signal which was produced by the transmitter and which includes information indicative of a channel evaluation signal and other control information to be used by the receiver, said extractor including an output coupled to said input for providing said channel evaluation signal and said other control information in response to said composite signal, said extractor further including a plurality of demodulators coupled to said input and also coupled to respective demodulating codes for demodulating said composite signal with each of said demodulating codes, said demodulating codes respectively indicative of a plurality of control indications possibly included in said other control information; and

a receive interface coupled to said extractor input for interfacing between said extractor and the transmission channel.

10. The receiver of claim 9, wherein said extractor includes accumulators respectively coupled to said demodulators to calculate respective sums in response to output signals received from the respective demodulators.

11. The receiver of claim 10, wherein said extractor includes a selector having an input coupled to said accumulators to receive therefrom said sums and responsive to said sums for providing said channel evaluation signal and said other control information, said selector coupled to said extractor output to provide thereto said channel evaluation signal and said other control information.

12. The receiver of claim 11, wherein said extractor includes a plurality of buffers respectively coupled to said demodulators to receive therefrom and store the respective demodulator output signals, wherein one of said demodulator output signals includes said channel evaluation signal, and wherein said selector compares said sums and provides a control output responsive to said comparison for indicating which of the demodulator output signals in said buffers includes said channel evaluation signal.

13. The receiver of claim 9, wherein the transmission channel includes a CDMA transmission channel of a cellular telecommunications system.

14. The receiver of claim 9, wherein the transmission channel is a radio channel and said evaluation signal includes pilot symbols used to evaluate the radio channel.

15. The receiver of claim 14, wherein said other control information includes power control information used in controlling transmission power in the radio channel.

16. A method of transmitting communication signals to a receiver via a transmission channel, comprising:

providing a channel evaluation signal and other control information to be used by the receiver; and

generating in response to the channel evaluation signal and the other control information a composite signal in which said other control information is embedded exclusively in said channel evaluation signal, and from which the receiver can determine the channel evaluation signal and the other control information.

17. The method of claim 16, wherein said generating step includes modulating said channel evaluation signal with encoded information representative of said other control information.

18. The method of claim 16, including sending said composite signal to the receiver via the transmission channel using less transmission time over the transmission channel than would be needed to send said channel evaluation signal and said other control information as separate signals.

19. The method of claim 16, including sending the composite signal to the receiver via the transmission channel using less transmission power than would be needed to send said channel evaluation signal and said other control information as separate signals.

20. The method of claim 16, including sending said composite signal to the receiver via the transmission channel, wherein said sending step creates less interference in the transmission channel than would be created by sending said channel evaluation signal and said other control information as separate signals.

21. The method of claim 16, wherein the transmission channel includes a CDMA transmission channel of a cellular telecommunications system.

22. The method of claim 16, wherein the transmission channel is a radio channel and said channel evaluation signal includes pilot symbols used to evaluate the radio channel.

23. The method of claim 22, wherein said other control information includes power control information used in controlling transmission power in the radio channel.

24. A method of operating a receiver to receive communication signals from a transmitter via a transmission channel, comprising:

receiving a composite signal produced by the transmitter and including information indicative of a channel evaluation signal and other control information to be used by the receiver; and

demodulating said composite signal with respective demodulating codes, wherein said demodulating codes are indicative of plurality of control indications possibly included in the other control information, in order to extract the channel evaluation signal and the other control information from the composite signal.

25. The method of claim 24, wherein said extracting step includes calculating respective sums in response to respective output signals produced in said step of demodulating said composite signal with respective demodulating codes.

26. The method of claim 25, wherein said extracting step includes providing the channel evaluation signal and the other control information in response to said sums.

27. The method of claim 26, wherein said extracting step includes storing respective output signals produced by said step of demodulating said composite signal with respective demodulating codes, said providing step including determining from a comparison of said sums that one of said stored output signals includes said composite signal, and selecting said one stored output signal.

28. The method of claim 24, wherein the transmission channel includes a CDMA transmission channel of a cellular telecommunications system.

29. The method of claim 24, wherein the transmission channel is a radio channel and said channel evaluation signal includes pilot symbols used to evaluate the radio channel.

30. The method of claim 29, wherein said other control information includes power control information used in controlling transmission power in the radio channel.