stds-802-16-tg3: TG3 draft COMMENT: 802.16.3c-01/59
> [Submitter's Last Name]
> Regev
>
> [Submitter's First Name]
> Einan
>
> [Starting Page #]
> 8
>
> [Starting Line #]
> 13
>
> [(T)echnical for Content-Related Material; (E)ditorial for typos,
> grammar, etc.]
> T
>
> [Detailed Description of Proposed Insertion, Deletion, Change]
> Replace the sub-title "PHY Design Considerations" by "OFDM PHY Concept"
>
> [Reason for Edit]
> A technical specification document which is in the normative part of the
> standard, should not contain general considerations but only a description
>
> of what is actually contained in the standard. Thus there is no place for
> design
> consideration at this part.
>
>
> [Submitter's Last Name]
> Regev
>
> [Submitter's First Name]
> Einan
>
> [Starting Page #]
> 8
>
> [Starting Line #]
> 27
>
> [(T)echnical for Content-Related Material; (E)ditorial for typos,
> grammar, etc.]
> T
>
> [Detailed Description of Proposed Insertion, Deletion, Change]
> Replace the body of clause 7.4.3 by the following substitution:
> "The scrambling function is designed to spread the energy of the
> information
> bits, over the entire spectrum of the signal, as to create a completely
> "white"
> spectrum. The importance of this function is different for receiver and
> transmitter: At the transmitter, the energy spread over the spectrum is
> essential in order to achieve the required spectral shape of the
> transmitted
> analog signal. On the other hand, at the receiver side it maximizes the
> performance of synchronization and detection function."
>
> [Reason for Edit]
> The design consideration should be omitted because it is not relevant to
> the normative part of the spec. Also the original explanation was missing
> a major role of the scrambler: randomization to avoid spectral
> irregularity.
>
> [Submitter's Last Name]
> Regev
>
> [Submitter's First Name]
> Einan
>
> [Starting Page #]
> 9
>
> [Starting Line #]
> 7
>
> [(T)echnical for Content-Related Material; (E)ditorial for typos,
> grammar, etc.]
> T
>
> [Detailed Description of Proposed Insertion, Deletion, Change]
> Replace the text:
> "The performance in non-additive white Gaussian noise (AWGN)
> environments can be significant design concern. For example, correcting
> burst
> errors can reduce the need for retransmissions, which can have a dramatic
> effect on TCP throughput. This needs to be understood in the context of
> time
> and frequency dispersion in a channel. The amount of coding gain required
> may
> be influenced by other factors, such as SINR enhancements provided via
> spatial,
> spectral, or temporal processing. As such, the amount of coding gain may
> differ
> between the forward and reverse links.
> In addition to channel coding, interleaving is used to mitigate against
> fast
> fading."
>
> by the substitution:
> "The performance in different channel conditions (other than AWGN) is a
> significant design consideration, especially the performance in frequency
> selective faded channels. In some cases, coding effect should be
> understood
> in the context of other signal processing receiver techniques used by the
> system (such as diversity, space-time processing etc.). The amount of
> coding
> gain required may differ between uplink and downlink due to the different
> propagation characteristics these channels may have."
>
> [Reason for Edit]
> The original text is not clear and accurate, and contains some phrases
> that
> can be seen as an subjective perception (the burst error correction
> example)
> - whether it is true or not.
>
>
> [Submitter's Last Name]
> Regev
>
> [Submitter's First Name]
> Einan
>
> [Starting Page #]
> 9
>
> [Starting Line #]
> 27
>
> [(T)echnical for Content-Related Material; (E)ditorial for typos,
> grammar, etc.]
> T
>
> [Detailed Description of Proposed Insertion, Deletion, Change]
> Remove the text in lines 27, 28, 29 and add the following text instead:
> "When using a multi-carrier modulation, each carrier can be modulated by
> changing it's amplitude and phase."
>
> [Reason for Edit]
> This phrase is completely general and has no contribution to the
> understanding of the PHY concept (which is the role of this whole
> chapter). It uses the term "water pouring" which is not explained,
> referred to or used in other parts of the standard. The last line should
> be added as it is a principal property of the modulation and should be
> described.
>
> [Submitter's Last Name]
> Regev
>
> [Submitter's First Name]
> Einan
>
> [Starting Page #]
> 9
>
> [Starting Line #]
> 31
>
> [(T)echnical for Content-Related Material; (E)ditorial for typos,
> grammar, etc.]
> T
>
> [Detailed Description of Proposed Insertion, Deletion, Change]
> Replace the body of clause 7.4.7 by the following substitution:
> "The time frequency map takes modulated data and maps it into specific
> sub-carriers, according to a defined mapping scheme. The time frequency
> map
> function should be able to identify the input data origin, in order to be
> able
> to perform mapping of a data stream containing data from different
> sources. As
> an example: An input data stream may contain MAC originated data bits,
> coming
> from different users, and PHY control information altogether. The MAP will
>
> identify data origin (user 1, user 2, etc.., PHY control…) and MAP each
> data
> stream into it's specified sub-carriers."
>
> [Reason for Edit]
> In the original phrase, the time/frequency map is defined as:
> "The time/frequency map implements the time and frequency aspects of a
> framing
> structure."
> This definition does not tell much about the function. In addition, the
> original phrase uses to many mixed examples in the description, that does
> not clarify, or are based on some previous knowledge that is not expected
> to be needed when reading a brief description.