SECOND AMENDMENT AND CONSENT

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                                                                   Exhibit 10.22

                          SECOND AMENDMENT AND CONSENT

     THIS SECOND AMENDMENT AND CONSENT (this "Amendment") is made and entered
into as of the 26 day of April 2006 by and among Clearwire Corporation, a
Delaware corporation, f.k.a. Flux U.S. Corporation ("Clearwire"), and ITFS
Spectrum Consultants LLC, a Delaware limited liability company ("ISC").

                                     RECITAL

     Clearwire and ISC are parties to that certain Spectrum Acquisition
Consulting Agreement dated February 1, 2005 ("SACA") pursuant to which ISC
agreed to introduce Clearwire to third parties and to facilitate the acquisition
of ITFS, MDS and MMDS spectrum through lease or purchase from such parties, and
Clearwire agreed in connection with such acquisitions or leases to grant to ISC
Consulting Consideration (defined in the SACA) upon the satisfaction of certain
conditions, including that ISC facilitate the execution of definitive agreements
and, with respect to a license purchase, lease or sublease, the closing of the
transaction with such third party as requested by Clearwire.

                                    AGREEMENT

     In consideration of the premises, the mutual covenants and promises made
below, and other good and valuable consideration, the parties agree as follows:

     1. Amendments to SACA. The SACA shall be amended as follows:

     A. SECTION 1(B) shall be amended by deleting the term "Consulting
Compensation" in the first sentence and replacing such term with "Consulting
Consideration."

     B. SECTION 3(B) shall be deleted in its entirety and shall be replaced with
the following new Section 3(b):

          "(b) CALCULATION OF CONSULTING CONSIDERATION. The consulting
     consideration ("Consulting Consideration") payable shall be calculated by
     multiplying the number of CPOPs in the applicable geographic service area
     ("GSA") times the applicable "Per CPOP ISC Consideration" determined as
     follows:

          (i) For the markets listed on Schedule 3(b)(i):

                                   Per CPOP ISC
                                  Consideration
                                  -------------
                                      $0.025

          (ii) For the Acquisition reflected in that certain EBS Excess Capacity
     Use and Royalty Agreement by and between Clearwire Spectrum Holdings LLC
     and District Board of Trustees of Valencia Community College, Florida:

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                                    Per CPOP ISC
                                  Consideration
                                  -------------
                                      $0.005

          (iii) For all other markets:

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