Wireless communication device and method for multi-MCS OFDM transmissions at different transmission power levels

• US 9,729,268 B2
• Filed: 12/05/2011
• Issued: 08/08/2017
• Est. Priority Date: 08/05/2011
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Kenney, Thomas J., Perahia, Eldad
• Primary Examiner(s): Lai, Andrew
• Assistant Examiner(s): Rahman, M Mostazir
• Application Number:
  US13/993,304
• Publication Number:
  US 20150295676A1
• Time in Patent Office: 2,073 Days
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 27/2627 Modulators
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range

Abstract

Embodiments of a wireless communication device and method for multi-MCS OFDM transmissions at different transmission power levels are generally described herein. In some embodiments, the wireless communication device may have a multi-MCS OFDM transmitter that is configured to encode data for transmission over two or more RF channels with a single encoding scheme to generate an encoded data stream. The transmitter may segment bits of the encoded data stream into a bit stream for each of the RF channels based on a selected modulation level for each of the two or more RF channels. A separate time-domain multicarrier waveform may be concurrently transmitted on each of the two or more RF channels at a power level that is selected not to exceed a maximum allowable transmit power level for that RF channel. The modulation level for each RF channel may be selected based at least in part on the maximum allowable transmit power level for that RF channel.

Claims

1. A wireless communication device comprising a memory;

and, a multi-modulation and coding schemes (MCS) orthogonal frequency division multiplexed (OFDM) transmitter coupled to the memory, wherein the multi-MCS OFDM transmitter comprises;

at least one radio frequency (RF) chain associated with a single transmit antenna; and

a variable gain element associated with the at least one of the RF chain to configure separate time-domain multicarrier waveform of an RF channel to have a power level that is selected to support a predetermined performance level and to not exceed a maximum allowable transmit power level for that RF channel, the multi-MCS OFDM transmitter configured to;

encode data for transmission over two or more RF channels with a single encoding scheme to generate an encoded data stream;

segment bits of the encoded data stream into a bit stream for each of the two or more RF channels based on a selected modulation level for each of the two or more RF channels; and

concurrently transmit the separate time-domain multicarrier waveform on each of the two or more RF channels at a power level that is selected not to exceed a maximum allowable transmit power level for each of the two or more RF channels, wherein the selected modulation level for each of the two or more RF channels is selected based at least in part on the maximum allowable transmit power level for each of the two or more RF channels, wherein the separate time-domain multicarrier waveforms are concurrently transmitted on each of the two or more RF channels, wherein for each RF channel of the two or more RF channels, the power level for each separate time-domain multicarrier waveform is selected so that for each of the two or more RF channels the power level does not exceed the maximum allowable transmit power level for each of the two or more RF channels, and wherein the multi-MCS OFDM transmitter configures each RF channel of the two or more RF channels to have a transmission bandwidth of approximately 1 MHz or 2 MHz by down-clocking a clock signal, wherein the separate time-domain multicarrier waveform transmitted on each of the two or more RF channels is an OFDM signal that comprises a plurality of subcarriers, and wherein one or more of the two or more RF channels occupy spectrum between approximately 700 MHz and 1000 MHz.

2. The wireless communication device of claim 1, wherein a first of the two or more RF channels has a lower maximum allowable transmit power level and a second of the two or more RF channels has a higher maximum allowable transmit power level, wherein based on a difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power level, paired modulation levels are selected for the first of the two or RF channels and the second of the two or more RF channels such that a power level difference between the paired modulation levels to support a predetermined quality level does not to exceed the difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power levels.

3. The wireless communication device of claim 2, wherein the multi-MCS OFDM transmitter comprises an encoder associated with each antenna of the plurality of antennas, the encoders being configurable to allow data to be encoded for transmission by each of the plurality of the antennas with a different encoding scheme, and wherein the multi-MCS OFDM transmitter is configured to concurrently transmit a separate time-domain multicarrier waveform on each of the two or more RF channels with a single one of the plurality of antennas.

4. The wireless communication device of claim 3, wherein greater modulation levels are selected for RF channels of the two or more RF channels having a higher allowed transmit power level and lower modulation levels are selected for RF channels of the two or more RF channels having a lower allowed transmit power level.

5. The wireless communication device of claim 3, further configured to receive signals from an access point that indicates the two or more RF channels and the maximum allowable transmit power level for each of the two or more RF channels.

6. The wireless communication device of claim 3, wherein the multi-MCS OFDM transmitter is further configured to:

map segmented data intended for each of the two or more RF channels to constellation symbols based as on the selected modulation level;

perform an inverse discrete Fourier transform (IDFT) on the constellation symbols for each of the two or more RF channels to generate a time-domain multicarrier waveform for each of the two or more RF channels;

reduce a transmit power level of the time-domain multicarrier waveforms associated with a higher power level higher modulation level channel to meet a predetermined performance level; and

combine the time-domain multicarrier waveform of each of the two or more RF channels for concurrent transmission on a single antenna of the plurality of antennas.

7. The wireless communication device of claim 1, wherein the two or more RF channels are adjacent RF channels within a spectrum.

8. The wireless communication device of claim 1, wherein the two or more RF channels are non-contiguous RF channels within a spectrum.

9. A method for multi-modulation level transmissions comprising:

encoding data for transmission over two or more radio frequency (RF) channels with a single encoding scheme to generate an encoded data stream;

segmenting bits of the encoded data stream into a bit stream for each of the two or more RF channels based on a selected modulation level for each of the two or more RF channels;

concurrently transmitting a separate time-domain multicarrier waveform on each of the two or more RF channels at a power level that is selected not to exceed a maximum allowable transmit power level for each of the two or more RF channels, wherein the selected modulation level for each of the two or more RF channels is selected based at least in part on the maximum allowable transmit power level for each of the two or more RF channels, wherein the separate time-domain multicarrier waveforms are concurrently transmitted on each of the two or more RF channels of the two or more RF channels, wherein for each RF channel of the two or more RF channels, the power level for each separate time-domain multicarrier waveform is selected so that for each of the two or more RF channels the power level does not exceed the maximum allowable transmit power level for each of the two or more RF channels;

configuring separate time-domain multicarrier waveform for each of the two or more RF channels to have a power level that is selected to support a predetermined performance level and to not exceed the maximum allowable transmit power level for of a corresponding RF channel of the two or more RF channels; and

configuring each RF channel of the two or more RF channels to have a transmission bandwidth of approximately 1 MHz or 2 MHz by down-clocking a clock signal, wherein the separate time-domain multicarrier waveform transmitted on each of the two or more RF channels is an OFDM signal that comprises a plurality of subcarriers, and wherein one or more of the two or more RF channels occupy spectrum between approximately 700 MHz and 1000 MHz.

10. The method of claim 9, wherein a first of the two or more RF channels has a lower maximum allowable transmit power level and a second of the two or more RF channels has a higher maximum allowable transmit power level, wherein based on a difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power level, the method includes selecting paired modulation levels for the two or more RF channels such that a power level difference between the paired modulation levels to support a predetermined quality level does not to exceed the difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power levels.

11. The method of claim 10 wherein the encoding data is configurable to allow data to be encoded for transmission by each of the plurality antennas with a different encoding scheme, and wherein the method further includes concurrently transmitting a separate time-domain multicarrier waveform on each of the two or more RF channels with a single one of the plurality of antennas.

12. The method of claim 10, wherein greater modulation levels are selected for RF channels of the two or more RF channels having a higher allowed transmit power level and lower modulation levels are selected for RF channels of the two or more RF channels having a lower allowed transmit power level.

13. A wireless communication device comprising:

a cellular transceiver for communicating with base stations of a cellular network in accordance with cellular communication techniques; and

a wireless network transceiver for communicating with access points of wireless network in accordance with a wireless network communication technique at frequencies between 700 MHz and 1000 MHz, wherein upper-level layers of the wireless communication device are configured to offload data communications from the cellular network to an available wireless network, wherein the wireless network transceiver is a multi-modulation and coding schemes (MCS) orthogonal frequency division multiplexed (OFDM) transmitter comprising;

at least one radio frequency (RF) chain associated with a single transmit antenna; and

a variable gain element associated with the at least one of the RF chain to configure separate time-domain multicarrier waveform of an RF channel to have a power level that is selected to support a predetermined performance level and to not exceed a maximum allowable transmit power level for that RF channel, the multi-MCS OFDM transmitter configured to;

encode data for transmission over two or more RF channels with a single encoding scheme to generate an encoded data stream; and

concurrently transmit a separate time-domain multicarrier waveform on each of the two or more RF channels at a power level that is selected not to exceed a maximum allowable transmit power level for each of the two or more RF channels, wherein a modulation level for each RF channel of the two or more RF channels is selected based at least in part on the maximum allowable transmit power level for each of the two or more RF channels, wherein the separate time-domain multicarrier waveforms are concurrently transmitted on each of the two or more RF channels, wherein for each RF channel of the two or more RF channels, the power level for each separate time-domain multicarrier waveform is selected so that for each of the two or more RF channels the power level does not exceed the maximum allowable transmit power level, and wherein the multi-MCS OFDM transmitter configures each RF channel of the two or more RF channels to have a transmission bandwidth of approximately 1 MHz or 2 MHz by down-clocking a clock signal, wherein the separate time-domain multicarrier waveform transmitted on each of the two or more RF channels is an OFDM signal that comprises a plurality of subcarriers, and wherein one or more of the two or more RF channels occupy spectrum between approximately 700 MHz and 1000 MHz.

14. The wireless communication device of claim 13, wherein the multi-MCS OFDM transmitter is further configured to segment bits of the encoded data stream into a bit stream for each of the RF channels of the two or more RF channels based on the selected modulation level for each of the two or more RF channels, wherein a first of the RF channels has a lower maximum allowable transmit power level and a second of the RF channels has a higher maximum allowable transmit power level, and wherein based on a difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power level, the method includes selecting paired modulation levels for the RF channels of the two or more RF channels such that a power level difference between the paired modulation levels to support a predetermined quality level does not exceed the difference between the higher maximum allowable transmit power level and the lower maximum allowable transmit power levels.

15. The wireless communications device of claim 13, wherein the wireless communication device comprises a smart phone having a touch screen.