CN-114270996-B - Filling and backoff operations when transmitting via multiple frequency bins in WLAN

CN114270996BCN 114270996 BCN114270996 BCN 114270996BCN-114270996-B

Abstract

A communication device determines that simultaneous transmission and reception via multiple frequency bins is not allowed in a WLAN. The communication device transmits a first packet in a first frequency segment starting at a first time and transmits a second packet in a second frequency segment starting at a second time different from the first time. The transmission of the second packet overlaps in time with the transmission of the first packet. In response to having determined that simultaneous transmission and reception via the plurality of frequency bins is not permitted, the communication device includes padding in the first packet such that an end of transmission of the first packet occurs at the same time as an end of transmission of the second packet.

Inventors

CHU LIWEN
ZHANG HONGYUAN
CAO RUI
Lou Huilian
ZHANG YAN

Assignees

马维尔亚洲私人有限公司

Dates

Publication Date: 20260508
Application Date: 20200619
Priority Date: 20190619

Claims (12)

1. A method for transmitting in multiple frequency bins simultaneously, comprising: Determining, at a communication device, whether a first start of a first transmission by the communication device in a first one of a plurality of frequency bins is to be synchronized with a second start of a second transmission by the communication device in a second one of the plurality of frequency bins; Performing, at the communication device, a backoff operation corresponding to the first frequency segment, the backoff operation involving decrementing a first backoff counter associated with the first frequency segment, wherein the first frequency segment is associated with a first medium access control, MAC, address of the communication device; Determining, at the communication device, whether the first back-off counter expires; determining, at the communication device, whether a second backoff counter that is decremented in relation to the second frequency segment has expired, wherein the second frequency segment is associated with a second medium MAC address of the communication device, the second medium MAC address being different from the first MAC address; In response to i) determining that the first start of the first transmission in the first frequency segment is to be synchronized with the second start of the second transmission in the second frequency segment, and ii) the first back-off counter expiring before the second back-off counter expires: Waiting for the second backoff counter to expire at the communication device to transmit a first packet in the first frequency segment, and At the same start time associated with expiration of the second back-off counter, transmission of the first packet by the communication device in the first frequency segment and transmission of a second packet in the second frequency segment is started.
2. The method of claim 1, further comprising: Decrementing, by the communication device, the backoff counter when the subchannel in the first frequency segment is determined to be idle, and When the subchannel in the first frequency segment is determined to be busy, suspending, by the communication device, the decrementing of the first back-off counter.
3. The method of claim 2, further comprising: in combination with determining that the first back-off counter has expired, determining, at the communication device, whether one or more other sub-channels in the first frequency segment are idle for a predetermined period of time before a respective transmission in the respective frequency segment begins; Wherein concurrently transmitting the respective transmissions in the respective frequency segments beginning at the same time is further responsive to determining that the one or more other sub-channels in the first frequency segment are idle for the predetermined period of time.
4. A method according to claim 3, further comprising: In response to determining that one or more other sub-channels in the first frequency bin are busy during the predetermined period, determining to defer simultaneous ones of the respective transmissions in the respective frequency bins.
5. The method of any of claims 1-4, wherein subsequent simultaneous transmissions in multiple frequency bins are combined: selecting, at the communication device, another frequency segment that is different from the first frequency segment; Performing, at the communication device, another backoff operation corresponding to the another frequency bin different from the first frequency bin, the another backoff operation comprising decrementing a particular second backoff counter of the first backoff counter or the one or more second backoff counters that is related to the another frequency bin; Determining, at the communication device, whether the first back-off counter or the particular second back-off counter expires, and In response to determining that the first back-off counter or the particular second back-off counter has expired, the subsequent simultaneous transmission is performed by the communication device in the plurality of frequency bins.
6. The method of any of claims 1-4, wherein determining whether the first start of the first transmission in the first frequency segment by the communication device is to be synchronized with the second start of the second transmission in the second frequency segment is based on: A distance in frequency between the first frequency bin and the second frequency bin.
7. A communication device, comprising: A wireless network interface device configured to communicate via a plurality of frequency segments, the wireless network interface device comprising one or more integrated circuit, IC, devices and a plurality of backoff counters implemented on the one or more IC devices, wherein the one or more IC devices are configured to: determining whether a first start of a first transmission by the wireless network interface device in a first frequency segment of the plurality of frequency segments is to be synchronized with a second start of a second transmission by the wireless network interface device in a second frequency segment of the plurality of frequency segments; performing a backoff operation corresponding to the first frequency bin, the backoff operation involving decrementing a first backoff counter of the plurality of backoff counters associated with the first frequency bin, wherein the first frequency bin is associated with a first medium access control, MAC, address of the communication device, Determining whether the first back-off counter has expired, Determining whether a second back-off counter of the plurality of back-off counters that is decremented in relation to the second frequency bin has expired, wherein the second frequency bin is associated with a second media MAC address of the communication device, the second media MAC address being different from the first MAC address, and In response to i) determining that the first start of the first transmission in the first frequency segment is to be synchronized with the second start of the second transmission in the second frequency segment, and ii) the first back-off counter expiring before the second back-off counter expires: waiting for the second back-off counter to expire to transmit a first packet in the first frequency band, and The wireless network interface device is controlled to start the first packet in the first frequency segment and the second packet in the second frequency segment at the same start time associated with expiration of the second back-off counter.
8. The communication device of claim 7, wherein the one or more IC devices are further configured to: decrementing the first back-off counter when the sub-channel in the first frequency segment is determined to be idle, and When the subchannel in the first frequency bin is determined to be busy, decrementing the first back-off counter is suspended.
9. The communication device of claim 8, wherein the one or more IC devices are further configured to: In combination with determining that the first back-off counter has expired, determining whether one or more other sub-channels in the first frequency segment are idle for a predetermined period of time before a corresponding transmission in the corresponding frequency segment begins, and Controlling the wireless network interface device to concurrently transmit the respective transmissions in the respective frequency segments is also responsive to determining that the one or more other sub-channels in the first frequency segment are idle for the predetermined period of time.
10. The communication device of claim 9, wherein the one or more IC devices are further configured to: In response to determining that one or more other sub-channels in the first frequency bin are busy during the predetermined period, determining to defer simultaneous ones of the respective transmissions in the respective frequency bins.
11. The communication device of any of claims 7-10, wherein the one or more IC devices are further configured to combine subsequent simultaneous transmissions in a plurality of frequency bins, Selecting another frequency segment different from the first frequency segment; Performing another backoff operation corresponding to the another frequency bin different from the first frequency bin, the another backoff operation comprising decrementing a specific second backoff counter associated with the another frequency bin among the first backoff counter or the one or more second backoff counters; determining whether the first back-off counter or the particular second back-off counter expires, and In response to determining that the first backoff counter or the particular second backoff counter has expired, controlling the wireless network interface device to perform the subsequent simultaneous transmission in the plurality of frequency segments.
12. The communication device of any of claims 7-10, wherein the one or more IC devices are further configured to determine whether a first start of the first transmission by the communication device in the first frequency segment is to be synchronized with the second start of the second transmission in the second frequency segment based on a distance in frequency between the first frequency segment and the second frequency segment.

Description

Filling and backoff operations when transmitting via multiple frequency bins in WLAN Cross Reference to Related Applications The present application claims the benefit of U.S. provisional patent application No. 62/863699 entitled "Multi-Band operation: synchronized and Unsynchronized," filed on 6/19 of 2019, the entire contents of which are incorporated herein by reference. Technical Field The present disclosure relates generally to wireless communication systems, and more particularly to simultaneous transmission and/or reception in multiple frequency bins in a Wireless Local Area Network (WLAN). Background Wireless Local Area Networks (WLANs) have evolved rapidly over the last two decades, and the development of WLAN standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards, has improved single user peak data rates. One way to increase the data rate is to increase the frequency bandwidth of the communication channel used in the WLAN. For example, the IEEE 802.11n standard allows two 20MHz sub-channels to be aggregated to form a 40MHz aggregated communication channel, while the newer IEEE 802.11ax standard allows up to 8 20MHz sub-channels to be aggregated to form up to 160MHz aggregated communication channels. Now, work has been started on a new version of the IEEE 802.11 standard, which is known as the IEEE 802.11be standard or Extremely High Throughput (EHT) WLAN. The IEEE 802.11be standard may allow for the aggregation of up to 16 20MHz subchannels (or even more) to form an aggregate communication channel of up to 320MHz (or even wider aggregate communication channels). Furthermore, the IEEE 802.11be standard may allow for the aggregation of 20MHz subchannels in different frequency bins (e.g., separated by a frequency gap) to form respective communication links. Furthermore, the IEEE 802.11be standard may allow for the aggregation of 20MHz subchannels in different Radio Frequency (RF) bands to form a single aggregate channel, or may allow for the aggregation of 20MHz subchannels in different RF bands to form corresponding communication links. The current IEEE802.11 standard (referred to herein as the "IEEE802.11 standard" for simplicity) provides for a first communication device to transmit packets to a second communication device via a single communication channel. The IEEE802.11 standard also provides a mechanism for a device to determine whether a single communication channel is busy or idle to determine whether the device can transmit in the single communication channel. Disclosure of Invention In one embodiment, a method for simultaneous transmission in multiple frequency bins includes determining, at a communication device, that simultaneous transmission and reception via multiple frequency bins is not allowed, transmitting, by the communication device, a first packet in a first frequency bin beginning at a first time, transmitting, by the communication device, a second packet in a second frequency bin beginning at a second time different from the first time, wherein transmission of the second packet overlaps in time with transmission of the first packet, and including padding in the first packet in response to having determined that simultaneous transmission and reception via multiple frequency bins is not allowed, such that an end of transmission of the first packet occurs at the same time as an end of transmission of the second packet. In another embodiment, the first communication device includes a wireless network interface device configured to communicate via a plurality of frequency segments. The wireless network interface device includes one or more Integrated Circuit (IC) devices configured to determine that simultaneous transmission and reception via a plurality of frequency bins is not allowed, control the wireless network interface device to transmit a first packet in a first frequency bin beginning at a first time, control the wireless network interface device to transmit a second packet in a second frequency bin beginning at a second time different from the first time, wherein transmission of the second packet overlaps in time with transmission of the first packet, and include padding in the first packet in response to having determined that simultaneous transmission and reception via the plurality of frequency bins is not allowed, such that an end of transmission of the first packet occurs at the same time as an end of transmission of the second packet. In yet another embodiment, a method for concurrently transmitting in a plurality of frequency bins includes performing, at a communication device, a backoff operation corresponding to one of the plurality of frequency bins, the backoff operation involving decrementing a backoff counter associated with the one frequency bin, determining, at the communication device, whether the backoff counter of the communication device has expired, and concurrently transmitting, by the communication