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Thus total L2/L3 signaling overhead would be (4-76+5+3+5=)-59 octets ! So we actually have gain - thanks to RoHC compression. Gain in data rate due to compression would be (59*8/75376=) 0.63 % and maximum data rate offered by LTE stack would be ( (75376+59x8)/1 ms=) 75.848 Mbps !
For 4x4 antenna configuration, data rate value would be 301.44 Mbps.
Conclusion
In this article, we were able to estimate maximum data rates at 75 Mbps to 300 Mbps. Would these data rates be possible in field ? It is easy to answer "No", but it is equally tough to answer "Then how much data rates would actually be possible in field ?"
Various factors would affect the data rates in field: use of OFDM in mobility scenarios (OFDM is still new technology in mobile wireless), frequencies away from NLOS range of frequencies and closer to LOS frequencies (making signal reception difficult), signaling plane overhead (more number of users, more will be amount of transmission spent on setup/modify/release/handover signaling), more retransmissions if signal quality not good (due to interefence, corruption etc.), lower modulation order and more redundant coding if signal quality not good enough, complexity in implementation of multi-antenna transmission (it is complex and much less predictable) etc.
On the other hand, techniques like adaptive modulation and coding, HARQ, would compensate for few losses and help improve the effective data rates in field.
Detailed discussion on all above factors is outside the scope of this article.
LTE has long way to go, but we have seen major improvements in user experience in 3G/UMTS compared to 2G/GPRS, so it would not be optimistic to say that 4G/LTE would bring user experience in mobile wireless world really close to its wireline counterpart !
References
[1] 3GPP TS 36.211, Rel 8 "Physical Channels and Modulation"
[2] 3GPP TS 36.212, Rel 8 "Multiplexing and Channel Coding"
[3] 3GPP TS 36.213, Rel 8 "Physical Layer Procedures"
[4] 3GPP TS 36.300, Rel 8 "E-UTRAN overall description"
[5] 3G Evolution: HSPA and LTE by Dahlman, Parkvall, Sköld, and Beming
[6] 3GPP TS 36.323, Rel 8 "PDCP"
[7] 3GPP TS 36.322, Rel 8 "RLC"
[8] 3GPP TS 36.321, Rel 8 "MAC"
[9] IETF rfc3095 "RoHC profiles: RTP,UDP"
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