Table of Contents. DigRF FAQ July, 2007

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1 Table of Contents 1 Knowing DigRF What is DigRF? What are the benefits of interface standardization? Who defines the DigRF standard? The goals of DigRF v3 are: What are the DigRF standards in use? Where can I obtain a copy of the standards? Brief explanation of the DigRF 1.12 standard: Brief explanation of the DigRF v3 standard: The DigRF 1.12 Interface The DigRF v3 Interface Agilent DigRF Solution What are the differences between DigRF 1.12 and DigRF v3? What type of test scenarios exist for DigRF? Does Agilent provide support for both versions of DigRF? What are the configurations for DigRF v3? Why are special probes needed for DigRF v3? N4850A and N4860 Technical Summary Why you need Agilent s DigRFv3 solution! What is so unique to Agilent DigRF solution? Are there other companies who provide this type of solution? DigRF v3 Solution information DigRF v3 Design Guide DigRF v3 Solutions Brochure N4850A / N4860A Product Data Sheet... 8

2 1 Knowing DigRF DigRF FAQ July, What is DigRF? DigRF is a Digital Serial Interface standard between RF-IC and BB-IC used in mobile handsets. The Digital Serial Interface replaces the analog interface in previous generation mobile handset architectures. The primary purpose of DigRF is to standardize the interfaces between RFIC and BBIC to ultimately produce Plug and play ICs from various vendors. 1.2 What are the benefits of interface standardization? Efficiency: reduce development efforts and cost Open market: interchangeable components Flexibility: provide wide range of features and capabilities 1.3 Who defines the DigRF standard? The DigRF Standards were defined by the DigRF Consortium group members. A list of those members can be found on the opening pages of the DigRF Standards. This member list includes many of the Mobile Handset IC vendors and Integrators. The DigRF working group was assimilated as a MIPI Alliance working group in April The group is focused on developing specifications for wireless mobile RFIC to BBIC interfaces in mobile devices. 1.4 The goals of DigRF are: Interoperability between BB-ICs and RF-ICs Reduce Cost (lower pin counts) Extend battery life Additionally, DigRF v3 provides a higher bandwidth interface to accommodate the higher data rates of 3GPP signals. 1.5 What are the DigRF standards in use? DigRF 1.12 (Publicly released) DigRF v3.xx (Privately released to DigRF consortium members only) 1.6 Where can I obtain a copy of the standards? The DigRF 1.12 standard is available for downloading at The DigRF v3 standard is not public and may only be obtained by consortium members.

3 1.7 Brief explanation of the DigRF 1.12 standard: The DigRF 1.12 standard supports the 2-2.5G air standards such as GSM and EDGE. The basic physical layer of this standard is implemented with an eightwire interface. IQ (Payload) Data is contained on a bi-directional interface (RxTxData) with an accompanying RxTxEn line, using a dedicated clock line, SysClk (with SysClkEn) to clock the data back and forth between RFIC and BBIC. Control data (CtrlData) is on a separate line with a dedicated control clock (CtrlClk) and CtrlClkEn line. A strobe line is typically used for over the air timing. All signals are single-ended. 1.8 Brief explanation of the DigRF v3 standard: The DigRF v3 standard supports a variety of 2-2.5G and 3GPP air standards. The basic physical layer of DigRF v3 standard is implemented with a six wire interface. Independent transmit (TxData) and receive (RxData) differential signal pairs allow for bi-directional communication (including both control and IQ/payload data) between the RF-IC and the BB-IC. SysClk and SysClkEn provide the timing references for digital serial data transmission and recovery. There is no strobe signal for over-the-air timing; this is accomplished via frame communication.

4 1.9 The DigRF 1.12 Interface DigRF FAQ July, The DigRF v3 Interface

5 2 Agilent DigRF Solution 2.1 What are the differences between DigRF 1.12 and DigRF v3? DigRF G (TDMA) only (GSM, EDGE, EGPRS) IQ data with padding (zeros) Serial Data Bi-directional Fairly simple interfaces or with B4602A and 89601A DigRF Version 3 (v3) 3G and 2.5G IQ data frames multiplexed with control data frames. Serial Data Bi-directional (Full duplex-separate RX/TX lines) Complex interfaces Differential Signaling Not backward compatible with DigRF 1.12 Needs special hardware to probe (N4850A and N4860A) 2.2 What type of test scenarios exist for DigRF? There are three basic test scenarios: RF-IC Validation, BB-IC Turn-on and RF- IC / BB-IC Integration. Refer to Agilent N4850A DigRF v3 Acquisition Probe N4860A DigRF v3 Stimulus Probe for more in-depth explanations on these test scenarios. 2.3 Does Agilent provide support for both versions of DigRF? Yes, though protocol analysis is not currently provided for DigRF 1.12 as it is for DigRFv3. Protocol analysis for DigRF 1.12 can be implemented by the user with the B4161A protocol development kit. The configuration for DigRF 1.12 requires just a Logic Analyzer with the B4602A Signal Extractor A VSA software is used for vector signal analysis to look at parameters such as EVM, Constellation position etc. Configuration for DigRFv3 is noted below.

6 2.4 What are the configurations for DigRF v3? This is dependent on the test scenario: 1. Acquisition only-stimulus provided by user, or for system integrators who do not plan on independently testing the BBIC and RFIC: Minimum 68 channel Logic Analyzer N4850A Acquisition probe (the packet decoder and B4602A signal extractor licenses are included) 2. Acquisition and Stimulus for independently testing BBIC or RFIC: Minimum 68 channel Logic Analyzer with 16720A pattern generator N4850A Acquisition probe (the packet decoder and B4602A signal extractor licenses are included) N4860A Stimulus probe Refer to the DigRF v3 Solutions Brochure (Lit # EN) for comprehensive DigRF v3 solutions. 2.5 Why are special probes needed for DigRF v3? Lack of Data Clock. The DigRF v3 interface (in particular) does not utilize a data clock, that is, there is no clock across the interface that is edge-coherent with the data. Thus, when probing, clock recovery circuitry must be available to properly clock the data into the logic analyzer. Voltage levels. There are three different voltage levels called out in the standard (generally only one is used on any given IC design). Thus both the analysis probe and the stimulus probe must accommodate all three at a minimum. Clock Speed. There is a SysClk-but as with voltage levels, there are three possible SysClk speeds allowable by the standard. Thus any probing must be able to take all three clock speeds into account (at a minimum). Speed changes. The DigRF interface incorporates several different speeds-and these change on the fly. It is absolutely necessary for any Test & Measurement equipment to track and keep up with this these speed changes. 2.6 N4850A and N4860 Technical Summary Supported for 2.5G and 3GPP air standards: GSM, EDGE, CDMA, cdma2000, W-CDMA, HSPA etc. Will support diversity, multiple Tx / Rx Supported voltage levels: 1.8V LVDS, 1.2V LVDS, SLVDS Speed: Up to 312Mbps Modes: Sleep, Low Speed, Med (RFIC Only),High Speed Tracks and reports rates changes during transmission

7 3 Why you need Agilent s DigRFv3 solution! 3.1 What is so unique to Agilent DigRF solution? Agilent has decades of experience in both Digital and RF test and measurement equipment. Agilent is uniquely qualified for the emergence of Digital Wireless and is the only company who can provide this type of cross domain solution. 3.2 Are there other companies who provide this type of solution? No. Agilent is the only test and measurement company to provide a solution for DigRF v3.

8 4 DigRF v3 Solution information DigRF FAQ July, DigRF v3 Design Guide Agilent N4850A/N4860A Digital Probes for DigRF v3 Design Guide Agilent is the only in the market having this type of design guide to assist you on DigRF v DigRF v3 Solutions Brochure Agilent Solutions for the DigRF v3 Digital Serial Interface Used In Mobile Wireless Devices 4.3 N4850A / N4860A Product Data Sheet Agilent N4850A DigRF v3 Acquisition Probe N4860A DigRF v3 Stimulus Probe