by Andrew J. Shepherd
Sprint 4G Rollout Updates
Thursday, March 28, 2013 - 10:10 AM MDT

Update: The Samsung review embargo has been lifted overnight, and Galaxy S4 reviews are being published around the Web today. Thanks to one of our favorite, highly thorough reviewers, Brian Klug at AnandTech, we can confirm that the Galaxy S4 follows the recent HTC One in providing a removable micro-SIM. So, while two data points do not necessarily a trend make, the One and Galaxy S4 do suggest that removable SIMs for Sprint LTE handsets are here to stay.

Arguably the most hotly anticipated handset of the year, rivaling even the next iPhone, the Samsung Galaxy S4 in its Sprint variant popped up in the FCC OET (Office of Engineering and Technology) database late yesterday, meaning that the next Galaxy is now authorized to operate in the US and is likely just a few weeks away from a Sprint street date. Not a revolutionary overhaul of the very successful Galaxy S3 platform of last year, the Galaxy S4 maintains a strong family resemblance to its older sibling but does generally and for Sprint specifically add a number of evolutionary enhancements, such as a larger 1080p display, world roaming capability, wireless charging cover functionality, and some transmit power increases.

Thus, adding to S4GRU's long standing series of articles on the FCC OET authorizations for the HTC EVO 4G LTE, Samsung Galaxy S3, Motorola Photon Q 4G, LG Optimus G, Samsung Galaxy Note 2, and HTC One is our run through of the RF capabilities of the Galaxy S4:

• CDMA1X + EV-DO band classes 0, 1, 10 (i.e. CDMA1X + EV-DO 850/1900/800)
• LTE band 25 (i.e. LTE 1900; PCS A-G blocks)
• LTE 5 MHz FDD carrier bandwidth
• LTE UE category 3
• W-CDMA bands 2, 5 (i.e. W-CDMA 1900/850)
• GSM 850/1900
• 802.11a/b/g/n/ac Wi-Fi
• 802.11n MCS index 7, 40 MHz carrier bandwidth
• 802.11ac MCS index 9, 80 MHz carrier bandwidth
• SVLTE support, including SVLTE and simultaneous 802.11b/g/n Wi-Fi tether
• RF ERP/EIRP maximum: 25.39 dBm (CDMA1X/EV-DO 850), 23.25 dBm (CDMA1X/EV-DO 1900), 24.62 dBm (CDMA1X/EV-DO 800), 22.83 dBm (LTE 1900)
• NFC antenna integrated into battery cover
• CDMA1X/EV-DO Rx antenna diversity
• Antenna locations: (see FCC OET diagram below)
• Simultaneous transmission paths: (see FCC OET diagram below)

Breaking down the RF specs, honestly, the Galaxy S4 may come across as a disappointment to many. That is primarily, though, because the reality could hardly live up to the expectations.

First, the Galaxy S4 does not support band 26 LTE 800 nor band 41 TD-LTE 2600. Reports are that Sprint will not release any dual band LTE devices and will skip straight to tri band. Those devices, however, are still at least six months off, so like all Sprint LTE devices before it, the Galaxy S4 is limited to band 25 LTE 1900 on the native Sprint network.

Additionally, the Galaxy S4's band 25 LTE 1900 is limited to 5 MHz FDD bandwidth. This seems to be largely a Samsung quirk, as Sprint LTE devices from other OEMs are tested and authorized for 10 MHz FDD (or greater) as well. That being said, this will likely be of no consequence, as all Sprint LTE FDD deployment for at least the next several years is apt to remain based on 5 MHz FDD carriers.

Also, unlike the recent HTC One, the Galaxy S4 does not appear to be particularly optimized for the Sprint LTE network. Using the FCC OET authorization documents, we can gauge a device's RF prowess by examining its maximum transmit ERP/EIRP and at what frequency that max occurs. This is by no means a perfect simulacrum for both transmission and reception, but we can say that Galaxy S4 LTE is at its max RF wise in the traditional PCS A-F blocks, not the PCS G block 1912.5 MHz center frequency where Sprint is deploying its initial LTE carrier nationwide.

Staying on ERP/EIRP discussion, the Galaxy S4 looks to be a rather strong performer on roaming CDMA1X/EV-DO 850 and the now being deployed Sprint native CDMA1X 800. Both show quite high ERP. On the flip side, the EIRP for CDMA1X/EV-DO 1900 is good, too, but oddly less than the ERP of the CDMA2000 airlinks below 1 GHz that enjoy significant propagation advantages. With most other handsets, the transmit power relationship is reversed, CDMA1X/EV-DO 1900 transmit power being greater to compensate for its greater path loss.

Furthermore, ERP/EIRP was tested with both the standard battery cover and the wireless charging cover. A definite caveat, the wireless charging cover reduces ERP/EIRP by up to 6 dB. Most likely, the induction coil in the wireless charging cover absorbs some of the transmitted RF, thus reducing the radiated power. For some users, the convenience of wireless charging may outweigh the hit to wireless performance. But S4GRU cannot generally recommend wireless charging due to its inefficiency (much power is wasted as heat) and detriment to RF.

As for simultaneous voice and data, the Galaxy S4 does support SVLTE but is the latest in a long line of Sprint LTE handsets now to forgo SVDO. Realistically, this comes as no great surprise, as we have not seen SVDO capability in any new handset since last summer. Either this is a limitation of the Qualcomm MDM9615 baseband modem that has become standard equipment or SVDO is no longer a strong priority as Sprint LTE coverage grows weekly. Regardless, CDMA1X and EV-DO share a transmit path (indicated in the FCC OET diagram above); hence, simultaneous CDMA1X voice and EV-DO data is not supported.

As S4GRU has reported in the past, the FCC OET authorization documents are not required to disclose world phone capabilities because those bands are not in use in the US. However, the presence of GSM 850/1900 and W-CDMA bands 2, 5 (i.e. W-CDMA 1900/850) is strongly indicative of the inclusion of international roaming capabilities, too. Indeed, other outlets are reporting that all variants of the Galaxy S4 include at a minimum quad band GSM 850/900/1800/1900 and W-CDMA bands 1, 2, 5, 8 (i.e. W-CDMA 2100+1900/1900/850/900) -- the latter supporting DC-HSPA+ on the downlink and HSUPA on the uplink. While we cannot confirm these reports at this time, they certainly do seem plausible. What also remains unconfirmed at this point is the SIM situation: embedded or removable. As soon as this info comes to light, we will update the article.

Source: FCC