Nonblocking OVSF Codes for 3G Wireless and Beyond Systems
نویسنده
چکیده
Orthogonal variable spreading factor (OVSF) codes are employed in the third generation (3G) wideband code division multiple access (WCDMA) wireless system as channelization codes. Any two OVSF codes of different tree levels are orthogonal if and only if one of two codes is not mother code of the other. This results in a major drawback of OVSF codes, called blocking property: when an OVSF code is assigned, it blocks all of its ancestor and descendant codes from assignment because they are not orthogonal to each other. This paper presents nonblocking OVSF (NOVSF) codes that are orthogonal to each other. Therefore, no NOVSF code blocks the assignment of any other NOVSF code.
منابع مشابه
Non-blocking OVSF codes and enhancing network capacity for 3G wireless and beyond systems
Orthogonal variable spreading factor (OVSF) codes are employed as channelization codes in WCDMA. Any two OVSF codes are orthogonal if and only if one of them is not a parent code of the other. Therefore, when an OVSF code is assigned, it blocks all of its ancestor and descendant codes from assignment because they are not orthogonal to each other. Unfortunately, this code blocking problem of OVS...
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