Channel determination method and wireless communication apparatus

• US 9,479,318 B2
• Filed: 06/27/2014
• Issued: 10/25/2016
• Est. Priority Date: 06/28/2013
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Suwa, Yutaka
• Primary Examiner(s): Acolatse, Kodzovi
• Application Number:
  US14/318,037
• Publication Number:
  US 20150003344A1
• Time in Patent Office: 851 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 5/0062 Avoidance of ingress interference, e.g. ham radio channels
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

A channel determination method is disclosed that can avoid performance deterioration caused by interference even in a situation in which radio waves from other communication apparatuses including a microwave oven using the same frequency band are mixed. This method detects a predetermined preamble in a received signal when performing carrier sensing while switching between reception frequencies of a receiving section. The method examines, using a counter, how often electric field strength exceeds a predetermined threshold for each channel during the carrier sensing, disables, upon detecting a signal from another 802.11 apparatus, a channel from which the signal is detected and also disables a channel for which the counter shows a count value exceeding the threshold.

Claims

1. A channel determination method in a carrier sensing operation performing a signal receiving operation while switching between reception frequencies of a receiving section, the method comprising:

detecting a predetermined preamble in received data during the carrier sensing operation;

detecting, when the predetermined preamble is detected, whether or not a received signal is a predetermined beacon;

disabling, when the predetermined preamble is detected in the received data and the received signal is detected to be the predetermined beacon, the channel from which the preamble is detected;

disabling a number of channels adjacent to the channel from which the preamble is detected, the number corresponding to a signal level of the signal from which the preamble is detected;

determining, when the predetermined preamble is not detected in the received data, whether or not electric field strength of the received signal exceeds a predetermined threshold;

causing the counter to count up when the electric field strength of the received signal exceeds the predetermined threshold and causing the counter to count down when the electric field strength of the received signal does not exceed the predetermined threshold for each channel; and

disabling each channel when the count value of the counter of a corresponding one of the channels reaches a predetermined value.

2. A channel determination method in a carrier sensing operation performing a signal receiving operation while switching between reception frequencies of a receiving section, the method comprising:

detecting a predetermined preamble in received data during the carrier sensing operation;

detecting, when the predetermined preamble is detected, whether or not a received signal is a predetermined beacon;

accumulating a clear channel assessment (CCA) value calculated based on information on signal intensity of the received signal relating to the channel from which the preamble is detected and recording the accumulated CCA value as a cumulative CCA value in a recording section;

disabling, when the predetermined preamble is detected in the received data and the received signal is detected to be the predetermined beacon, the channel from which the preamble is detected;

disabling a number of channels adjacent to the channel from which the preamble is detected, the number corresponding to a signal level of the signal from which the preamble is detected; and

determining, based on the cumulative CCA value, whether to enable or disable a channel from which the predetermined preamble is detected in the received data and in which the received signal is not detected to be the predetermined beacon.